Sure Death<\/h1>\r\n<\/div>\r\nThis anti-smoking photo (Figure 13.6.1) clearly makes the point that smoking causes death. The image is not using hyperbole, because smoking actually is<\/em> deadly. It causes about\u00a07\u00a0million deaths each year, and is the single greatest cause of preventable death worldwide. As many as half of all people who smoke tobacco die from it. As a result of smoking\u2019s deadly effects, the life expectancy of long-term smokers is significantly less than that of non-smokers. In fact, long-term smokers can expect their lifespan to be reduced by as much as 18 years, and they are three times\u00a0more\u00a0likely than non-smokers to die before the age of 70.\r\n\r\nWhy Is Smoking Deadly?<\/h1>\r\n<\/div>\r\nAs shown in Figure 13.6.2, tobacco smoking has adverse effects on just about every bodily system and organ. The detrimental health effects of smoking depend on the number of years that a person smokes and how much the person smokes. Contrary to popular belief, all forms of tobacco smoke \u2014 including smoke from cigars and tobacco pipes \u2014 have similar health risks as those of cigarette smoke. Smokeless tobacco may be less of a danger to the lungs and heart, but it, too, has serious health effects. It significantly increases the risk of cancers of the mouth and throat, among other health problems.\r\n\r\n[caption id=\"attachment_4364\" align=\"alignnone\" width=\"2048\"]![\"15.6.2](\"https:\/\/pressbooks.ccconline.org\/acchumanbio\/wp-content\/uploads\/sites\/152\/2023\/10\/Risks_from_smoking-smoking_can_damage_every_part_of_the_body-2.png\")
Figure 13.6.2 Smoking is known to cause many different cancers and chronic diseases.<\/em>[\/caption]\r\n\r\nEven non-smokers may not be spared the deadly risks of tobacco smoke. If you spend time around smokers either at home or on the job, then you are at risk of the dangers of secondhand smoke.\u00a0[pb_glossary id=\"4365\"]Secondhand smoke[\/pb_glossary]<\/strong> enters the air directly from burning cigarettes (and cigars and pipes), and indirectly from smokers' lungs. This smoke may linger in indoor air for hours, and it increases the risk of a wide range of adverse health effects.\u00a0According to Health Canada, second-hand smoke causes 800 deaths from lung cancer and heart disease in non-smokers every year. <\/span>The 2014 U.S. Surgeon General\u2019s Report concluded that there is no established risk-free level of exposure to secondhand smoke. Non-smokers who are exposed to secondhand smoke may have as much as a 30 per cent increase in their risk of lung cancer and heart disease.\u00a0<\/span>\r\n\r\nTobacco contains\u00a0[pb_glossary id=\"4366\"]nicotine[\/pb_glossary],<\/strong>\u00a0which is a psychoactive drug. Although nicotine in tobacco smoke does not directly cause [pb_glossary id=\"5605\"]cancer[\/pb_glossary] or most of the other health risks of smoking, it is a highly addictive drug.\u00a0Nicotine is actually even more addictive than cocaine or heroin. The addictive nature of nicotine explains why it is so difficult for smokers to quit the habit, even when they know the health risks and really\u00a0want<\/em>\u00a0to stop smoking. The good news is that if someone\u00a0does<\/em>\u00a0stop smoking, his or her risks of smoking-related diseases and death soon start to fall.\u00a0By one year after quitting, the risk of\u00a0heart\u00a0disease drops to only half of that of a continuing smoker.\r\n\r\nSmoking and Cancer<\/h1>\r\n<\/div>\r\nOne of the main health risks of smoking is cancer, particular cancer of the lung. Because of the increased risk of [pb_glossary id=\"4356\"]lung cancer[\/pb_glossary] with smoking, the risk of dying from lung cancer before age 85 is more than 20 times higher for a male smoker than for a male non-smoker. As the rate of smoking increases, so does the rate of lung cancer deaths, although the effects of smoking on lung cancer deaths can take up to 20 years to manifest themselves, as shown in Figure 13.6.3. Besides lung cancer, several other forms of cancer are also significantly more likely in smokers than non-smokers, including cancers of the kidney, larynx, mouth, lip, tongue, throat, bladder, esophagus, pancreas, and stomach. Unfortunately, many of these cancers have extremely low cure rates.\r\n\r\n[caption id=\"attachment_4367\" align=\"aligncenter\" width=\"705\"]![\"13.6.3](\"https:\/\/pressbooks.ccconline.org\/acchumanbio\/wp-content\/uploads\/sites\/152\/2023\/10\/Cancer_smoking_lung_cancer_correlation_from_NIH.svg_-2.png\")
Figure 13.6.3 Cigarette smoking by men in the U.S. began to decline in the 1950s, but it wasn\u2019t until the 1970s \u2014 roughly 20 years later \u2014 that this was reflected by a concomitant decline in lung cancer deaths in men.<\/em>[\/caption]\r\n\r\nWhen you consider the\u00a0composition\u00a0of tobacco smoke, it\u2019s not surprising that it increases the risk of cancer. Tobacco smoke contains dozens of chemicals proven to be carcinogens, or causes of cancer. Many of these chemicals bind to\u00a0DNA\u00a0in a smoker\u2019s\u00a0cells, and may either kill the cells or cause\u00a0mutations. If the mutations inhibit programmed cell death, the cells can survive to become cancer cells. Some of the most potent carcinogens in tobacco smoke include benzopyrene, acrolein, and nitrosamines. Other carcinogens in tobacco smoke are radioactive isotopes, including lead-210 and polonium-210.\r\n\r\nRespiratory Effects of Smoking<\/h1>\r\n<\/div>\r\nLong-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs' ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.\r\n\r\nCardiovascular Effects of Smoking<\/h1>\r\n<\/div>\r\nInhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of [pb_glossary id=\"4368\"]heart attack[\/pb_glossary] and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.\r\n\r\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.\r\n\r\nAdditional Adverse Health Effects of Smoking<\/h1>\r\n<\/div>\r\nA wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:\r\n\r\n \t- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\r\n \t
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\r\n \t
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\r\n \t
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\r\n \t
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\r\n \t
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\r\n \t
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\r\n \t
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\r\n<\/ul>\r\n\r\n
Feature: Human Biology in the News<\/h1>\r\n<\/div>\r\n\r\n[caption id=\"attachment_4369\" align=\"alignleft\" width=\"382\"]![\"13.6.4](\"https:\/\/pressbooks.ccconline.org\/acchumanbio\/wp-content\/uploads\/sites\/152\/2023\/10\/An_Electronic_Cigarette_11359245033-2.jpg\")
Figure 13.6.4 An E-Cigarette or Vape.<\/em>[\/caption]\r\n\r\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. [pb_glossary id=\"4370\"]E-cigarettes<\/span>[\/pb_glossary]<\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span>\r\n\r\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.\r\n\r\nSome manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers' attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don't contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.\r\n\r\n13.6 Summary<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The [pb_glossary id=\"4366\"]nicotine[\/pb_glossary] in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\r\n \t
- A major health risk of smoking is [pb_glossary id=\"5605\"]cancer[\/pb_glossary] of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as [pb_glossary id=\"4371\"]carcinogens[\/pb_glossary].<\/li>\r\n \t
- Smoking is the primary cause of [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of [pb_glossary id=\"4311\"]alveoli[\/pb_glossary] so the lungs can no longer fully exhale air.<\/li>\r\n \t
- Smoking damages the\u00a0[pb_glossary id=\"5927\"]cardiovascular system[\/pb_glossary]\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, [pb_glossary id=\"4368\"]heart attack[\/pb_glossary], and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\r\n \t
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Review Questions<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\r\n \t
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\r\n \t
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\r\n \t
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\r\n \t
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\r\n \t
- Explain how smoking causes COPD.<\/li>\r\n \t
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\r\n<\/ol>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Explore More<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\nhttps:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=emb_logo\r\nBlowing Smoke: The Lost Legacy of the Surgeon General's Report | Alan Blum | TEDxTuscaloosa, TEDx Talks, 2015.<\/p>\r\nhttps:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU\r\n
The dangers of vaping, RWJ Barnabas Health, 2019.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n \r\n
Attributions<\/h2>\r\nFigure 13.6.1<\/strong>\r\n\r\n\r\n\r\n\r\nCigarette<\/a>\u00a0by \u00a0Uitbundig<\/a>\u00a0on\u00a0Unsplash<\/a>\u00a0is used under the\u00a0Unsplash License<\/a>\u00a0(https:\/\/unsplash.com\/license<\/a>)\r\n\r\nFigure 13.6.2<\/strong>\r\n\r\nRisks_from_smoking-smoking_can_damage_every_part_of_the_body<\/a> by CDC<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.3<\/strong>\r\n\r\nCancer_smoking_lung_cancer_correlation_from_NIH.svg<\/a> by Sakurambo<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.4<\/strong>\r\n\r\nAn_Electronic_Cigarette_(11359245033)<\/a> by Lindsay Fox<\/a> from Newport beach, United States on Wikimedia Commons is used under a\u00a0CC BY 2.0<\/a> (https:\/\/creativecommons.org\/licenses\/by\/2.0) license.\r\n\r\n<\/div>\r\n<\/section>\r\nReferences<\/h2>\r\n
Allen, J. G., Flanigan, S. S., LeBlanc, M., Vallarino, J., MacNaughton, P., Stewart, J. H., Christiani, D.C. (2016, June 1). Flavoring chemicals in E-Cigarettes: Diacetyl, 2,3-Pentanedione, and Acetoin in a sample of 51 products, including fruit-, candy-, and cocktail-flavored E-cigarettes [online article]. Environmental Health Perspectives, 124:733\u2013739. <\/em>https:\/\/doi.org\/10.1289\/ehp.1510185<\/span><\/p>\r\nHealth Canada. (2015). Dangers of second-hand smoke [online article]. Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/smoking-tobacco\/avoid-second-hand-smoke\/second-hand-smoke\/dangers-second-hand-smoke.html<\/p>\r\n
RWJ Barnabas Health. (2019, September 25). The dangers of vaping. YouTube. https:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU&feature=youtu.be<\/p>\r\n
TEDx Talks. (2015, August 7). Blowing smoke: The lost legacy of the surgeon general's report | Alan Blum | TEDxTuscaloosa. https:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=youtu.be<\/p>\r\n
Tobacco and Vaping Products Act. (2016, June 26). Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/health-concerns\/tobacco\/legislation\/federal-laws\/tobacco-act.html<\/p>\r\n
Vaping, E-cigarettes to be regulated by Health Canada. (2016, November 22). CBC\/Radio-Canada. HTTP:\/\/www.cbc.ca\/news\/health\/vaping-health-canada-legislation-1.3862589<\/cite><\/span><\/p>\r\nWikipedia contributors. (2020, August 9). Regulation of electronic cigarettes. In\u00a0Wikipedia. <\/i>\u00a0https:\/\/en.wikipedia.org\/w\/index.php?title=Regulation_of_electronic_cigarettes&oldid=972059825<\/p>\r\n
<\/p>","rendered":"
<\/p>\n![\"Image](\"https:\/\/pressbooks.ccconline.org\/acchumanbio\/wp-content\/uploads\/sites\/152\/2019\/06\/photo-1622708037376-5cba1a57f735-2.jpg\")
Figure 13.6.1 Smoking kills.<\/em><\/figcaption><\/figure>\n\nSure Death<\/h1>\n<\/div>\n
This anti-smoking photo (Figure 13.6.1) clearly makes the point that smoking causes death. The image is not using hyperbole, because smoking actually is<\/em> deadly. It causes about\u00a07\u00a0million deaths each year, and is the single greatest cause of preventable death worldwide. As many as half of all people who smoke tobacco die from it. As a result of smoking\u2019s deadly effects, the life expectancy of long-term smokers is significantly less than that of non-smokers. In fact, long-term smokers can expect their lifespan to be reduced by as much as 18 years, and they are three times\u00a0more\u00a0likely than non-smokers to die before the age of 70.<\/p>\n\nWhy Is Smoking Deadly?<\/h1>\n<\/div>\n
As shown in Figure 13.6.2, tobacco smoking has adverse effects on just about every bodily system and organ. The detrimental health effects of smoking depend on the number of years that a person smokes and how much the person smokes. Contrary to popular belief, all forms of tobacco smoke \u2014 including smoke from cigars and tobacco pipes \u2014 have similar health risks as those of cigarette smoke. Smokeless tobacco may be less of a danger to the lungs and heart, but it, too, has serious health effects. It significantly increases the risk of cancers of the mouth and throat, among other health problems.<\/p>\nFigure 13.6.2 Smoking is known to cause many different cancers and chronic diseases.<\/em><\/figcaption><\/figure>\nEven non-smokers may not be spared the deadly risks of tobacco smoke. If you spend time around smokers either at home or on the job, then you are at risk of the dangers of secondhand smoke.\u00a0Secondhand smoke<\/a><\/strong> enters the air directly from burning cigarettes (and cigars and pipes), and indirectly from smokers’ lungs. This smoke may linger in indoor air for hours, and it increases the risk of a wide range of adverse health effects.\u00a0According to Health Canada, second-hand smoke causes 800 deaths from lung cancer and heart disease in non-smokers every year. <\/span>The 2014 U.S. Surgeon General\u2019s Report concluded that there is no established risk-free level of exposure to secondhand smoke. Non-smokers who are exposed to secondhand smoke may have as much as a 30 per cent increase in their risk of lung cancer and heart disease.\u00a0<\/span><\/p>\nTobacco contains\u00a0nicotine<\/a>,<\/strong>\u00a0which is a psychoactive drug. Although nicotine in tobacco smoke does not directly cause cancer<\/a> or most of the other health risks of smoking, it is a highly addictive drug.\u00a0Nicotine is actually even more addictive than cocaine or heroin. The addictive nature of nicotine explains why it is so difficult for smokers to quit the habit, even when they know the health risks and really\u00a0want<\/em>\u00a0to stop smoking. The good news is that if someone\u00a0does<\/em>\u00a0stop smoking, his or her risks of smoking-related diseases and death soon start to fall.\u00a0By one year after quitting, the risk of\u00a0heart\u00a0disease drops to only half of that of a continuing smoker.<\/p>\n\nSmoking and Cancer<\/h1>\n<\/div>\n
One of the main health risks of smoking is cancer, particular cancer of the lung. Because of the increased risk of lung cancer<\/a> with smoking, the risk of dying from lung cancer before age 85 is more than 20 times higher for a male smoker than for a male non-smoker. As the rate of smoking increases, so does the rate of lung cancer deaths, although the effects of smoking on lung cancer deaths can take up to 20 years to manifest themselves, as shown in Figure 13.6.3. Besides lung cancer, several other forms of cancer are also significantly more likely in smokers than non-smokers, including cancers of the kidney, larynx, mouth, lip, tongue, throat, bladder, esophagus, pancreas, and stomach. Unfortunately, many of these cancers have extremely low cure rates.<\/p>\nFigure 13.6.3 Cigarette smoking by men in the U.S. began to decline in the 1950s, but it wasn\u2019t until the 1970s \u2014 roughly 20 years later \u2014 that this was reflected by a concomitant decline in lung cancer deaths in men.<\/em><\/figcaption><\/figure>\nWhen you consider the\u00a0composition\u00a0of tobacco smoke, it\u2019s not surprising that it increases the risk of cancer. Tobacco smoke contains dozens of chemicals proven to be carcinogens, or causes of cancer. Many of these chemicals bind to\u00a0DNA\u00a0in a smoker\u2019s\u00a0cells, and may either kill the cells or cause\u00a0mutations. If the mutations inhibit programmed cell death, the cells can survive to become cancer cells. Some of the most potent carcinogens in tobacco smoke include benzopyrene, acrolein, and nitrosamines. Other carcinogens in tobacco smoke are radioactive isotopes, including lead-210 and polonium-210.<\/p>\n
\nRespiratory Effects of Smoking<\/h1>\n<\/div>\n
Long-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to chronic obstructive pulmonary disease<\/a> (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs’ ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.<\/p>\n\nCardiovascular Effects of Smoking<\/h1>\n<\/div>\n
Inhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of heart attack<\/a> and stroke<\/a>. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.<\/p>\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.<\/p>\n
\nAdditional Adverse Health Effects of Smoking<\/h1>\n<\/div>\n
A wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:<\/p>\n
\n- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\n
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\n
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\n
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\n
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\n
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\n
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\n
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\n<\/ul>\n\n
Feature: Human Biology in the News<\/h1>\n<\/div>\nFigure 13.6.4 An E-Cigarette or Vape.<\/em><\/figcaption><\/figure>\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. E-cigarettes<\/span><\/a><\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span><\/p>\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.<\/p>\n
Some manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers’ attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don’t contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.<\/p>\n\n\n13.6 Summary<\/span><\/h1>\n<\/header>\n\n\n- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The nicotine<\/a> in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\n
- A major health risk of smoking is cancer<\/a> of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as carcinogens<\/a>.<\/li>\n
- Smoking is the primary cause of chronic obstructive pulmonary disease<\/a> (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of alveoli<\/a> so the lungs can no longer fully exhale air.<\/li>\n
- Smoking damages the\u00a0cardiovascular system<\/a>\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, heart attack<\/a>, and stroke<\/a>. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\n
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n\n
\n13.6 Review Questions<\/span><\/h1>\n<\/header>\n\n\n- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\n
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\n
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\n
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\n
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\n
- Explain how smoking causes COPD.<\/li>\n
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\n<\/ol>\n<\/div>\n<\/div>\n\n
\n13.6 Explore More<\/span><\/h1>\n<\/header>\n\n
Why Is Smoking Deadly?<\/h1>\r\n<\/div>\r\nAs shown in Figure 13.6.2, tobacco smoking has adverse effects on just about every bodily system and organ. The detrimental health effects of smoking depend on the number of years that a person smokes and how much the person smokes. Contrary to popular belief, all forms of tobacco smoke \u2014 including smoke from cigars and tobacco pipes \u2014 have similar health risks as those of cigarette smoke. Smokeless tobacco may be less of a danger to the lungs and heart, but it, too, has serious health effects. It significantly increases the risk of cancers of the mouth and throat, among other health problems.\r\n\r\n[caption id=\"attachment_4364\" align=\"alignnone\" width=\"2048\"] Figure 13.6.2 Smoking is known to cause many different cancers and chronic diseases.<\/em>[\/caption]\r\n\r\nEven non-smokers may not be spared the deadly risks of tobacco smoke. If you spend time around smokers either at home or on the job, then you are at risk of the dangers of secondhand smoke.\u00a0[pb_glossary id=\"4365\"]Secondhand smoke[\/pb_glossary]<\/strong> enters the air directly from burning cigarettes (and cigars and pipes), and indirectly from smokers' lungs. This smoke may linger in indoor air for hours, and it increases the risk of a wide range of adverse health effects.\u00a0According to Health Canada, second-hand smoke causes 800 deaths from lung cancer and heart disease in non-smokers every year. <\/span>The 2014 U.S. Surgeon General\u2019s Report concluded that there is no established risk-free level of exposure to secondhand smoke. Non-smokers who are exposed to secondhand smoke may have as much as a 30 per cent increase in their risk of lung cancer and heart disease.\u00a0<\/span>\r\n\r\nTobacco contains\u00a0[pb_glossary id=\"4366\"]nicotine[\/pb_glossary],<\/strong>\u00a0which is a psychoactive drug. Although nicotine in tobacco smoke does not directly cause [pb_glossary id=\"5605\"]cancer[\/pb_glossary] or most of the other health risks of smoking, it is a highly addictive drug.\u00a0Nicotine is actually even more addictive than cocaine or heroin. The addictive nature of nicotine explains why it is so difficult for smokers to quit the habit, even when they know the health risks and really\u00a0want<\/em>\u00a0to stop smoking. The good news is that if someone\u00a0does<\/em>\u00a0stop smoking, his or her risks of smoking-related diseases and death soon start to fall.\u00a0By one year after quitting, the risk of\u00a0heart\u00a0disease drops to only half of that of a continuing smoker.\r\n\r\nSmoking and Cancer<\/h1>\r\n<\/div>\r\nOne of the main health risks of smoking is cancer, particular cancer of the lung. Because of the increased risk of [pb_glossary id=\"4356\"]lung cancer[\/pb_glossary] with smoking, the risk of dying from lung cancer before age 85 is more than 20 times higher for a male smoker than for a male non-smoker. As the rate of smoking increases, so does the rate of lung cancer deaths, although the effects of smoking on lung cancer deaths can take up to 20 years to manifest themselves, as shown in Figure 13.6.3. Besides lung cancer, several other forms of cancer are also significantly more likely in smokers than non-smokers, including cancers of the kidney, larynx, mouth, lip, tongue, throat, bladder, esophagus, pancreas, and stomach. Unfortunately, many of these cancers have extremely low cure rates.\r\n\r\n[caption id=\"attachment_4367\" align=\"aligncenter\" width=\"705\"] Figure 13.6.3 Cigarette smoking by men in the U.S. began to decline in the 1950s, but it wasn\u2019t until the 1970s \u2014 roughly 20 years later \u2014 that this was reflected by a concomitant decline in lung cancer deaths in men.<\/em>[\/caption]\r\n\r\nWhen you consider the\u00a0composition\u00a0of tobacco smoke, it\u2019s not surprising that it increases the risk of cancer. Tobacco smoke contains dozens of chemicals proven to be carcinogens, or causes of cancer. Many of these chemicals bind to\u00a0DNA\u00a0in a smoker\u2019s\u00a0cells, and may either kill the cells or cause\u00a0mutations. If the mutations inhibit programmed cell death, the cells can survive to become cancer cells. Some of the most potent carcinogens in tobacco smoke include benzopyrene, acrolein, and nitrosamines. Other carcinogens in tobacco smoke are radioactive isotopes, including lead-210 and polonium-210.\r\n\r\nRespiratory Effects of Smoking<\/h1>\r\n<\/div>\r\nLong-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs' ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.\r\n\r\nCardiovascular Effects of Smoking<\/h1>\r\n<\/div>\r\nInhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of [pb_glossary id=\"4368\"]heart attack[\/pb_glossary] and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.\r\n\r\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.\r\n\r\nAdditional Adverse Health Effects of Smoking<\/h1>\r\n<\/div>\r\nA wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:\r\n\r\n \t- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\r\n \t
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\r\n \t
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\r\n \t
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\r\n \t
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\r\n \t
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\r\n \t
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\r\n \t
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\r\n<\/ul>\r\n\r\n
Feature: Human Biology in the News<\/h1>\r\n<\/div>\r\n\r\n[caption id=\"attachment_4369\" align=\"alignleft\" width=\"382\"] Figure 13.6.4 An E-Cigarette or Vape.<\/em>[\/caption]\r\n\r\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. [pb_glossary id=\"4370\"]E-cigarettes<\/span>[\/pb_glossary]<\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span>\r\n\r\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.\r\n\r\nSome manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers' attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don't contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.\r\n\r\n13.6 Summary<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The [pb_glossary id=\"4366\"]nicotine[\/pb_glossary] in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\r\n \t
- A major health risk of smoking is [pb_glossary id=\"5605\"]cancer[\/pb_glossary] of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as [pb_glossary id=\"4371\"]carcinogens[\/pb_glossary].<\/li>\r\n \t
- Smoking is the primary cause of [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of [pb_glossary id=\"4311\"]alveoli[\/pb_glossary] so the lungs can no longer fully exhale air.<\/li>\r\n \t
- Smoking damages the\u00a0[pb_glossary id=\"5927\"]cardiovascular system[\/pb_glossary]\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, [pb_glossary id=\"4368\"]heart attack[\/pb_glossary], and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\r\n \t
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Review Questions<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\r\n \t
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\r\n \t
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\r\n \t
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\r\n \t
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\r\n \t
- Explain how smoking causes COPD.<\/li>\r\n \t
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\r\n<\/ol>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Explore More<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\nhttps:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=emb_logo\r\nBlowing Smoke: The Lost Legacy of the Surgeon General's Report | Alan Blum | TEDxTuscaloosa, TEDx Talks, 2015.<\/p>\r\nhttps:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU\r\n
The dangers of vaping, RWJ Barnabas Health, 2019.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n \r\n
Attributions<\/h2>\r\nFigure 13.6.1<\/strong>\r\n\r\n\r\n\r\n\r\nCigarette<\/a>\u00a0by \u00a0Uitbundig<\/a>\u00a0on\u00a0Unsplash<\/a>\u00a0is used under the\u00a0Unsplash License<\/a>\u00a0(https:\/\/unsplash.com\/license<\/a>)\r\n\r\nFigure 13.6.2<\/strong>\r\n\r\nRisks_from_smoking-smoking_can_damage_every_part_of_the_body<\/a> by CDC<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.3<\/strong>\r\n\r\nCancer_smoking_lung_cancer_correlation_from_NIH.svg<\/a> by Sakurambo<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.4<\/strong>\r\n\r\nAn_Electronic_Cigarette_(11359245033)<\/a> by Lindsay Fox<\/a> from Newport beach, United States on Wikimedia Commons is used under a\u00a0CC BY 2.0<\/a> (https:\/\/creativecommons.org\/licenses\/by\/2.0) license.\r\n\r\n<\/div>\r\n<\/section>\r\nReferences<\/h2>\r\n
Allen, J. G., Flanigan, S. S., LeBlanc, M., Vallarino, J., MacNaughton, P., Stewart, J. H., Christiani, D.C. (2016, June 1). Flavoring chemicals in E-Cigarettes: Diacetyl, 2,3-Pentanedione, and Acetoin in a sample of 51 products, including fruit-, candy-, and cocktail-flavored E-cigarettes [online article]. Environmental Health Perspectives, 124:733\u2013739. <\/em>https:\/\/doi.org\/10.1289\/ehp.1510185<\/span><\/p>\r\nHealth Canada. (2015). Dangers of second-hand smoke [online article]. Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/smoking-tobacco\/avoid-second-hand-smoke\/second-hand-smoke\/dangers-second-hand-smoke.html<\/p>\r\n
RWJ Barnabas Health. (2019, September 25). The dangers of vaping. YouTube. https:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU&feature=youtu.be<\/p>\r\n
TEDx Talks. (2015, August 7). Blowing smoke: The lost legacy of the surgeon general's report | Alan Blum | TEDxTuscaloosa. https:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=youtu.be<\/p>\r\n
Tobacco and Vaping Products Act. (2016, June 26). Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/health-concerns\/tobacco\/legislation\/federal-laws\/tobacco-act.html<\/p>\r\n
Vaping, E-cigarettes to be regulated by Health Canada. (2016, November 22). CBC\/Radio-Canada. HTTP:\/\/www.cbc.ca\/news\/health\/vaping-health-canada-legislation-1.3862589<\/cite><\/span><\/p>\r\nWikipedia contributors. (2020, August 9). Regulation of electronic cigarettes. In\u00a0Wikipedia. <\/i>\u00a0https:\/\/en.wikipedia.org\/w\/index.php?title=Regulation_of_electronic_cigarettes&oldid=972059825<\/p>\r\n
<\/p>","rendered":"
<\/p>\nFigure 13.6.1 Smoking kills.<\/em><\/figcaption><\/figure>\n\nSure Death<\/h1>\n<\/div>\n
This anti-smoking photo (Figure 13.6.1) clearly makes the point that smoking causes death. The image is not using hyperbole, because smoking actually is<\/em> deadly. It causes about\u00a07\u00a0million deaths each year, and is the single greatest cause of preventable death worldwide. As many as half of all people who smoke tobacco die from it. As a result of smoking\u2019s deadly effects, the life expectancy of long-term smokers is significantly less than that of non-smokers. In fact, long-term smokers can expect their lifespan to be reduced by as much as 18 years, and they are three times\u00a0more\u00a0likely than non-smokers to die before the age of 70.<\/p>\n\nWhy Is Smoking Deadly?<\/h1>\n<\/div>\n
As shown in Figure 13.6.2, tobacco smoking has adverse effects on just about every bodily system and organ. The detrimental health effects of smoking depend on the number of years that a person smokes and how much the person smokes. Contrary to popular belief, all forms of tobacco smoke \u2014 including smoke from cigars and tobacco pipes \u2014 have similar health risks as those of cigarette smoke. Smokeless tobacco may be less of a danger to the lungs and heart, but it, too, has serious health effects. It significantly increases the risk of cancers of the mouth and throat, among other health problems.<\/p>\nFigure 13.6.2 Smoking is known to cause many different cancers and chronic diseases.<\/em><\/figcaption><\/figure>\nEven non-smokers may not be spared the deadly risks of tobacco smoke. If you spend time around smokers either at home or on the job, then you are at risk of the dangers of secondhand smoke.\u00a0Secondhand smoke<\/a><\/strong> enters the air directly from burning cigarettes (and cigars and pipes), and indirectly from smokers’ lungs. This smoke may linger in indoor air for hours, and it increases the risk of a wide range of adverse health effects.\u00a0According to Health Canada, second-hand smoke causes 800 deaths from lung cancer and heart disease in non-smokers every year. <\/span>The 2014 U.S. Surgeon General\u2019s Report concluded that there is no established risk-free level of exposure to secondhand smoke. Non-smokers who are exposed to secondhand smoke may have as much as a 30 per cent increase in their risk of lung cancer and heart disease.\u00a0<\/span><\/p>\nTobacco contains\u00a0nicotine<\/a>,<\/strong>\u00a0which is a psychoactive drug. Although nicotine in tobacco smoke does not directly cause cancer<\/a> or most of the other health risks of smoking, it is a highly addictive drug.\u00a0Nicotine is actually even more addictive than cocaine or heroin. The addictive nature of nicotine explains why it is so difficult for smokers to quit the habit, even when they know the health risks and really\u00a0want<\/em>\u00a0to stop smoking. The good news is that if someone\u00a0does<\/em>\u00a0stop smoking, his or her risks of smoking-related diseases and death soon start to fall.\u00a0By one year after quitting, the risk of\u00a0heart\u00a0disease drops to only half of that of a continuing smoker.<\/p>\n\nSmoking and Cancer<\/h1>\n<\/div>\n
One of the main health risks of smoking is cancer, particular cancer of the lung. Because of the increased risk of lung cancer<\/a> with smoking, the risk of dying from lung cancer before age 85 is more than 20 times higher for a male smoker than for a male non-smoker. As the rate of smoking increases, so does the rate of lung cancer deaths, although the effects of smoking on lung cancer deaths can take up to 20 years to manifest themselves, as shown in Figure 13.6.3. Besides lung cancer, several other forms of cancer are also significantly more likely in smokers than non-smokers, including cancers of the kidney, larynx, mouth, lip, tongue, throat, bladder, esophagus, pancreas, and stomach. Unfortunately, many of these cancers have extremely low cure rates.<\/p>\nFigure 13.6.3 Cigarette smoking by men in the U.S. began to decline in the 1950s, but it wasn\u2019t until the 1970s \u2014 roughly 20 years later \u2014 that this was reflected by a concomitant decline in lung cancer deaths in men.<\/em><\/figcaption><\/figure>\nWhen you consider the\u00a0composition\u00a0of tobacco smoke, it\u2019s not surprising that it increases the risk of cancer. Tobacco smoke contains dozens of chemicals proven to be carcinogens, or causes of cancer. Many of these chemicals bind to\u00a0DNA\u00a0in a smoker\u2019s\u00a0cells, and may either kill the cells or cause\u00a0mutations. If the mutations inhibit programmed cell death, the cells can survive to become cancer cells. Some of the most potent carcinogens in tobacco smoke include benzopyrene, acrolein, and nitrosamines. Other carcinogens in tobacco smoke are radioactive isotopes, including lead-210 and polonium-210.<\/p>\n
\nRespiratory Effects of Smoking<\/h1>\n<\/div>\n
Long-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to chronic obstructive pulmonary disease<\/a> (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs’ ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.<\/p>\n\nCardiovascular Effects of Smoking<\/h1>\n<\/div>\n
Inhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of heart attack<\/a> and stroke<\/a>. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.<\/p>\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.<\/p>\n
\nAdditional Adverse Health Effects of Smoking<\/h1>\n<\/div>\n
A wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:<\/p>\n
\n- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\n
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\n
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\n
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\n
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\n
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\n
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\n
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\n<\/ul>\n\n
Feature: Human Biology in the News<\/h1>\n<\/div>\nFigure 13.6.4 An E-Cigarette or Vape.<\/em><\/figcaption><\/figure>\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. E-cigarettes<\/span><\/a><\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span><\/p>\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.<\/p>\n
Some manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers’ attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don’t contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.<\/p>\n\n\n13.6 Summary<\/span><\/h1>\n<\/header>\n\n\n- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The nicotine<\/a> in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\n
- A major health risk of smoking is cancer<\/a> of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as carcinogens<\/a>.<\/li>\n
- Smoking is the primary cause of chronic obstructive pulmonary disease<\/a> (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of alveoli<\/a> so the lungs can no longer fully exhale air.<\/li>\n
- Smoking damages the\u00a0cardiovascular system<\/a>\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, heart attack<\/a>, and stroke<\/a>. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\n
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n\n
\n13.6 Review Questions<\/span><\/h1>\n<\/header>\n\n\n- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\n
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\n
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\n
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\n
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\n
- Explain how smoking causes COPD.<\/li>\n
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\n<\/ol>\n<\/div>\n<\/div>\n\n
\n13.6 Explore More<\/span><\/h1>\n<\/header>\n\n
Smoking and Cancer<\/h1>\r\n<\/div>\r\nOne of the main health risks of smoking is cancer, particular cancer of the lung. Because of the increased risk of [pb_glossary id=\"4356\"]lung cancer[\/pb_glossary] with smoking, the risk of dying from lung cancer before age 85 is more than 20 times higher for a male smoker than for a male non-smoker. As the rate of smoking increases, so does the rate of lung cancer deaths, although the effects of smoking on lung cancer deaths can take up to 20 years to manifest themselves, as shown in Figure 13.6.3. Besides lung cancer, several other forms of cancer are also significantly more likely in smokers than non-smokers, including cancers of the kidney, larynx, mouth, lip, tongue, throat, bladder, esophagus, pancreas, and stomach. Unfortunately, many of these cancers have extremely low cure rates.\r\n\r\n[caption id=\"attachment_4367\" align=\"aligncenter\" width=\"705\"] Figure 13.6.3 Cigarette smoking by men in the U.S. began to decline in the 1950s, but it wasn\u2019t until the 1970s \u2014 roughly 20 years later \u2014 that this was reflected by a concomitant decline in lung cancer deaths in men.<\/em>[\/caption]\r\n\r\nWhen you consider the\u00a0composition\u00a0of tobacco smoke, it\u2019s not surprising that it increases the risk of cancer. Tobacco smoke contains dozens of chemicals proven to be carcinogens, or causes of cancer. Many of these chemicals bind to\u00a0DNA\u00a0in a smoker\u2019s\u00a0cells, and may either kill the cells or cause\u00a0mutations. If the mutations inhibit programmed cell death, the cells can survive to become cancer cells. Some of the most potent carcinogens in tobacco smoke include benzopyrene, acrolein, and nitrosamines. Other carcinogens in tobacco smoke are radioactive isotopes, including lead-210 and polonium-210.\r\n\r\nRespiratory Effects of Smoking<\/h1>\r\n<\/div>\r\nLong-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs' ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.\r\n\r\nCardiovascular Effects of Smoking<\/h1>\r\n<\/div>\r\nInhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of [pb_glossary id=\"4368\"]heart attack[\/pb_glossary] and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.\r\n\r\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.\r\n\r\nAdditional Adverse Health Effects of Smoking<\/h1>\r\n<\/div>\r\nA wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:\r\n\r\n \t- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\r\n \t
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\r\n \t
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\r\n \t
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\r\n \t
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\r\n \t
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\r\n \t
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\r\n \t
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\r\n<\/ul>\r\n\r\n
Feature: Human Biology in the News<\/h1>\r\n<\/div>\r\n\r\n[caption id=\"attachment_4369\" align=\"alignleft\" width=\"382\"] Figure 13.6.4 An E-Cigarette or Vape.<\/em>[\/caption]\r\n\r\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. [pb_glossary id=\"4370\"]E-cigarettes<\/span>[\/pb_glossary]<\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span>\r\n\r\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.\r\n\r\nSome manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers' attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don't contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.\r\n\r\n13.6 Summary<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The [pb_glossary id=\"4366\"]nicotine[\/pb_glossary] in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\r\n \t
- A major health risk of smoking is [pb_glossary id=\"5605\"]cancer[\/pb_glossary] of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as [pb_glossary id=\"4371\"]carcinogens[\/pb_glossary].<\/li>\r\n \t
- Smoking is the primary cause of [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of [pb_glossary id=\"4311\"]alveoli[\/pb_glossary] so the lungs can no longer fully exhale air.<\/li>\r\n \t
- Smoking damages the\u00a0[pb_glossary id=\"5927\"]cardiovascular system[\/pb_glossary]\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, [pb_glossary id=\"4368\"]heart attack[\/pb_glossary], and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\r\n \t
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Review Questions<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\r\n \t
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\r\n \t
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\r\n \t
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\r\n \t
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\r\n \t
- Explain how smoking causes COPD.<\/li>\r\n \t
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\r\n<\/ol>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Explore More<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\nhttps:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=emb_logo\r\nBlowing Smoke: The Lost Legacy of the Surgeon General's Report | Alan Blum | TEDxTuscaloosa, TEDx Talks, 2015.<\/p>\r\nhttps:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU\r\n
The dangers of vaping, RWJ Barnabas Health, 2019.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n \r\n
Attributions<\/h2>\r\nFigure 13.6.1<\/strong>\r\n\r\n\r\n\r\n\r\nCigarette<\/a>\u00a0by \u00a0Uitbundig<\/a>\u00a0on\u00a0Unsplash<\/a>\u00a0is used under the\u00a0Unsplash License<\/a>\u00a0(https:\/\/unsplash.com\/license<\/a>)\r\n\r\nFigure 13.6.2<\/strong>\r\n\r\nRisks_from_smoking-smoking_can_damage_every_part_of_the_body<\/a> by CDC<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.3<\/strong>\r\n\r\nCancer_smoking_lung_cancer_correlation_from_NIH.svg<\/a> by Sakurambo<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.4<\/strong>\r\n\r\nAn_Electronic_Cigarette_(11359245033)<\/a> by Lindsay Fox<\/a> from Newport beach, United States on Wikimedia Commons is used under a\u00a0CC BY 2.0<\/a> (https:\/\/creativecommons.org\/licenses\/by\/2.0) license.\r\n\r\n<\/div>\r\n<\/section>\r\nReferences<\/h2>\r\n
Allen, J. G., Flanigan, S. S., LeBlanc, M., Vallarino, J., MacNaughton, P., Stewart, J. H., Christiani, D.C. (2016, June 1). Flavoring chemicals in E-Cigarettes: Diacetyl, 2,3-Pentanedione, and Acetoin in a sample of 51 products, including fruit-, candy-, and cocktail-flavored E-cigarettes [online article]. Environmental Health Perspectives, 124:733\u2013739. <\/em>https:\/\/doi.org\/10.1289\/ehp.1510185<\/span><\/p>\r\nHealth Canada. (2015). Dangers of second-hand smoke [online article]. Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/smoking-tobacco\/avoid-second-hand-smoke\/second-hand-smoke\/dangers-second-hand-smoke.html<\/p>\r\n
RWJ Barnabas Health. (2019, September 25). The dangers of vaping. YouTube. https:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU&feature=youtu.be<\/p>\r\n
TEDx Talks. (2015, August 7). Blowing smoke: The lost legacy of the surgeon general's report | Alan Blum | TEDxTuscaloosa. https:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=youtu.be<\/p>\r\n
Tobacco and Vaping Products Act. (2016, June 26). Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/health-concerns\/tobacco\/legislation\/federal-laws\/tobacco-act.html<\/p>\r\n
Vaping, E-cigarettes to be regulated by Health Canada. (2016, November 22). CBC\/Radio-Canada. HTTP:\/\/www.cbc.ca\/news\/health\/vaping-health-canada-legislation-1.3862589<\/cite><\/span><\/p>\r\nWikipedia contributors. (2020, August 9). Regulation of electronic cigarettes. In\u00a0Wikipedia. <\/i>\u00a0https:\/\/en.wikipedia.org\/w\/index.php?title=Regulation_of_electronic_cigarettes&oldid=972059825<\/p>\r\n
<\/p>","rendered":"
<\/p>\nFigure 13.6.1 Smoking kills.<\/em><\/figcaption><\/figure>\n\nSure Death<\/h1>\n<\/div>\n
This anti-smoking photo (Figure 13.6.1) clearly makes the point that smoking causes death. The image is not using hyperbole, because smoking actually is<\/em> deadly. It causes about\u00a07\u00a0million deaths each year, and is the single greatest cause of preventable death worldwide. As many as half of all people who smoke tobacco die from it. As a result of smoking\u2019s deadly effects, the life expectancy of long-term smokers is significantly less than that of non-smokers. In fact, long-term smokers can expect their lifespan to be reduced by as much as 18 years, and they are three times\u00a0more\u00a0likely than non-smokers to die before the age of 70.<\/p>\n\nWhy Is Smoking Deadly?<\/h1>\n<\/div>\n
As shown in Figure 13.6.2, tobacco smoking has adverse effects on just about every bodily system and organ. The detrimental health effects of smoking depend on the number of years that a person smokes and how much the person smokes. Contrary to popular belief, all forms of tobacco smoke \u2014 including smoke from cigars and tobacco pipes \u2014 have similar health risks as those of cigarette smoke. Smokeless tobacco may be less of a danger to the lungs and heart, but it, too, has serious health effects. It significantly increases the risk of cancers of the mouth and throat, among other health problems.<\/p>\nFigure 13.6.2 Smoking is known to cause many different cancers and chronic diseases.<\/em><\/figcaption><\/figure>\nEven non-smokers may not be spared the deadly risks of tobacco smoke. If you spend time around smokers either at home or on the job, then you are at risk of the dangers of secondhand smoke.\u00a0Secondhand smoke<\/a><\/strong> enters the air directly from burning cigarettes (and cigars and pipes), and indirectly from smokers’ lungs. This smoke may linger in indoor air for hours, and it increases the risk of a wide range of adverse health effects.\u00a0According to Health Canada, second-hand smoke causes 800 deaths from lung cancer and heart disease in non-smokers every year. <\/span>The 2014 U.S. Surgeon General\u2019s Report concluded that there is no established risk-free level of exposure to secondhand smoke. Non-smokers who are exposed to secondhand smoke may have as much as a 30 per cent increase in their risk of lung cancer and heart disease.\u00a0<\/span><\/p>\nTobacco contains\u00a0nicotine<\/a>,<\/strong>\u00a0which is a psychoactive drug. Although nicotine in tobacco smoke does not directly cause cancer<\/a> or most of the other health risks of smoking, it is a highly addictive drug.\u00a0Nicotine is actually even more addictive than cocaine or heroin. The addictive nature of nicotine explains why it is so difficult for smokers to quit the habit, even when they know the health risks and really\u00a0want<\/em>\u00a0to stop smoking. The good news is that if someone\u00a0does<\/em>\u00a0stop smoking, his or her risks of smoking-related diseases and death soon start to fall.\u00a0By one year after quitting, the risk of\u00a0heart\u00a0disease drops to only half of that of a continuing smoker.<\/p>\n\nSmoking and Cancer<\/h1>\n<\/div>\n
One of the main health risks of smoking is cancer, particular cancer of the lung. Because of the increased risk of lung cancer<\/a> with smoking, the risk of dying from lung cancer before age 85 is more than 20 times higher for a male smoker than for a male non-smoker. As the rate of smoking increases, so does the rate of lung cancer deaths, although the effects of smoking on lung cancer deaths can take up to 20 years to manifest themselves, as shown in Figure 13.6.3. Besides lung cancer, several other forms of cancer are also significantly more likely in smokers than non-smokers, including cancers of the kidney, larynx, mouth, lip, tongue, throat, bladder, esophagus, pancreas, and stomach. Unfortunately, many of these cancers have extremely low cure rates.<\/p>\nFigure 13.6.3 Cigarette smoking by men in the U.S. began to decline in the 1950s, but it wasn\u2019t until the 1970s \u2014 roughly 20 years later \u2014 that this was reflected by a concomitant decline in lung cancer deaths in men.<\/em><\/figcaption><\/figure>\nWhen you consider the\u00a0composition\u00a0of tobacco smoke, it\u2019s not surprising that it increases the risk of cancer. Tobacco smoke contains dozens of chemicals proven to be carcinogens, or causes of cancer. Many of these chemicals bind to\u00a0DNA\u00a0in a smoker\u2019s\u00a0cells, and may either kill the cells or cause\u00a0mutations. If the mutations inhibit programmed cell death, the cells can survive to become cancer cells. Some of the most potent carcinogens in tobacco smoke include benzopyrene, acrolein, and nitrosamines. Other carcinogens in tobacco smoke are radioactive isotopes, including lead-210 and polonium-210.<\/p>\n
\nRespiratory Effects of Smoking<\/h1>\n<\/div>\n
Long-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to chronic obstructive pulmonary disease<\/a> (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs’ ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.<\/p>\n\nCardiovascular Effects of Smoking<\/h1>\n<\/div>\n
Inhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of heart attack<\/a> and stroke<\/a>. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.<\/p>\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.<\/p>\n
\nAdditional Adverse Health Effects of Smoking<\/h1>\n<\/div>\n
A wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:<\/p>\n
\n- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\n
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\n
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\n
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\n
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\n
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\n
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\n
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\n<\/ul>\n\n
Feature: Human Biology in the News<\/h1>\n<\/div>\nFigure 13.6.4 An E-Cigarette or Vape.<\/em><\/figcaption><\/figure>\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. E-cigarettes<\/span><\/a><\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span><\/p>\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.<\/p>\n
Some manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers’ attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don’t contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.<\/p>\n\n\n13.6 Summary<\/span><\/h1>\n<\/header>\n\n\n- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The nicotine<\/a> in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\n
- A major health risk of smoking is cancer<\/a> of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as carcinogens<\/a>.<\/li>\n
- Smoking is the primary cause of chronic obstructive pulmonary disease<\/a> (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of alveoli<\/a> so the lungs can no longer fully exhale air.<\/li>\n
- Smoking damages the\u00a0cardiovascular system<\/a>\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, heart attack<\/a>, and stroke<\/a>. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\n
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n\n
\n13.6 Review Questions<\/span><\/h1>\n<\/header>\n\n\n- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\n
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\n
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\n
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\n
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\n
- Explain how smoking causes COPD.<\/li>\n
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\n<\/ol>\n<\/div>\n<\/div>\n\n
\n13.6 Explore More<\/span><\/h1>\n<\/header>\n\n
Respiratory Effects of Smoking<\/h1>\r\n<\/div>\r\nLong-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs' ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.\r\n\r\nCardiovascular Effects of Smoking<\/h1>\r\n<\/div>\r\nInhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of [pb_glossary id=\"4368\"]heart attack[\/pb_glossary] and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.\r\n\r\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.\r\n\r\nAdditional Adverse Health Effects of Smoking<\/h1>\r\n<\/div>\r\nA wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:\r\n\r\n \t- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\r\n \t
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\r\n \t
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\r\n \t
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\r\n \t
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\r\n \t
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\r\n \t
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\r\n \t
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\r\n<\/ul>\r\n\r\n
Feature: Human Biology in the News<\/h1>\r\n<\/div>\r\n\r\n[caption id=\"attachment_4369\" align=\"alignleft\" width=\"382\"] Figure 13.6.4 An E-Cigarette or Vape.<\/em>[\/caption]\r\n\r\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. [pb_glossary id=\"4370\"]E-cigarettes<\/span>[\/pb_glossary]<\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span>\r\n\r\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.\r\n\r\nSome manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers' attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don't contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.\r\n\r\n13.6 Summary<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The [pb_glossary id=\"4366\"]nicotine[\/pb_glossary] in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\r\n \t
- A major health risk of smoking is [pb_glossary id=\"5605\"]cancer[\/pb_glossary] of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as [pb_glossary id=\"4371\"]carcinogens[\/pb_glossary].<\/li>\r\n \t
- Smoking is the primary cause of [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of [pb_glossary id=\"4311\"]alveoli[\/pb_glossary] so the lungs can no longer fully exhale air.<\/li>\r\n \t
- Smoking damages the\u00a0[pb_glossary id=\"5927\"]cardiovascular system[\/pb_glossary]\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, [pb_glossary id=\"4368\"]heart attack[\/pb_glossary], and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\r\n \t
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Review Questions<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\r\n \t
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\r\n \t
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\r\n \t
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\r\n \t
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\r\n \t
- Explain how smoking causes COPD.<\/li>\r\n \t
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\r\n<\/ol>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Explore More<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\nhttps:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=emb_logo\r\nBlowing Smoke: The Lost Legacy of the Surgeon General's Report | Alan Blum | TEDxTuscaloosa, TEDx Talks, 2015.<\/p>\r\nhttps:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU\r\n
The dangers of vaping, RWJ Barnabas Health, 2019.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n \r\n
Attributions<\/h2>\r\nFigure 13.6.1<\/strong>\r\n\r\n\r\n\r\n\r\nCigarette<\/a>\u00a0by \u00a0Uitbundig<\/a>\u00a0on\u00a0Unsplash<\/a>\u00a0is used under the\u00a0Unsplash License<\/a>\u00a0(https:\/\/unsplash.com\/license<\/a>)\r\n\r\nFigure 13.6.2<\/strong>\r\n\r\nRisks_from_smoking-smoking_can_damage_every_part_of_the_body<\/a> by CDC<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.3<\/strong>\r\n\r\nCancer_smoking_lung_cancer_correlation_from_NIH.svg<\/a> by Sakurambo<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.4<\/strong>\r\n\r\nAn_Electronic_Cigarette_(11359245033)<\/a> by Lindsay Fox<\/a> from Newport beach, United States on Wikimedia Commons is used under a\u00a0CC BY 2.0<\/a> (https:\/\/creativecommons.org\/licenses\/by\/2.0) license.\r\n\r\n<\/div>\r\n<\/section>\r\nReferences<\/h2>\r\n
Allen, J. G., Flanigan, S. S., LeBlanc, M., Vallarino, J., MacNaughton, P., Stewart, J. H., Christiani, D.C. (2016, June 1). Flavoring chemicals in E-Cigarettes: Diacetyl, 2,3-Pentanedione, and Acetoin in a sample of 51 products, including fruit-, candy-, and cocktail-flavored E-cigarettes [online article]. Environmental Health Perspectives, 124:733\u2013739. <\/em>https:\/\/doi.org\/10.1289\/ehp.1510185<\/span><\/p>\r\nHealth Canada. (2015). Dangers of second-hand smoke [online article]. Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/smoking-tobacco\/avoid-second-hand-smoke\/second-hand-smoke\/dangers-second-hand-smoke.html<\/p>\r\n
RWJ Barnabas Health. (2019, September 25). The dangers of vaping. YouTube. https:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU&feature=youtu.be<\/p>\r\n
TEDx Talks. (2015, August 7). Blowing smoke: The lost legacy of the surgeon general's report | Alan Blum | TEDxTuscaloosa. https:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=youtu.be<\/p>\r\n
Tobacco and Vaping Products Act. (2016, June 26). Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/health-concerns\/tobacco\/legislation\/federal-laws\/tobacco-act.html<\/p>\r\n
Vaping, E-cigarettes to be regulated by Health Canada. (2016, November 22). CBC\/Radio-Canada. HTTP:\/\/www.cbc.ca\/news\/health\/vaping-health-canada-legislation-1.3862589<\/cite><\/span><\/p>\r\nWikipedia contributors. (2020, August 9). Regulation of electronic cigarettes. In\u00a0Wikipedia. <\/i>\u00a0https:\/\/en.wikipedia.org\/w\/index.php?title=Regulation_of_electronic_cigarettes&oldid=972059825<\/p>\r\n
<\/p>","rendered":"
<\/p>\nFigure 13.6.1 Smoking kills.<\/em><\/figcaption><\/figure>\n\nSure Death<\/h1>\n<\/div>\n
This anti-smoking photo (Figure 13.6.1) clearly makes the point that smoking causes death. The image is not using hyperbole, because smoking actually is<\/em> deadly. It causes about\u00a07\u00a0million deaths each year, and is the single greatest cause of preventable death worldwide. As many as half of all people who smoke tobacco die from it. As a result of smoking\u2019s deadly effects, the life expectancy of long-term smokers is significantly less than that of non-smokers. In fact, long-term smokers can expect their lifespan to be reduced by as much as 18 years, and they are three times\u00a0more\u00a0likely than non-smokers to die before the age of 70.<\/p>\n\nWhy Is Smoking Deadly?<\/h1>\n<\/div>\n
As shown in Figure 13.6.2, tobacco smoking has adverse effects on just about every bodily system and organ. The detrimental health effects of smoking depend on the number of years that a person smokes and how much the person smokes. Contrary to popular belief, all forms of tobacco smoke \u2014 including smoke from cigars and tobacco pipes \u2014 have similar health risks as those of cigarette smoke. Smokeless tobacco may be less of a danger to the lungs and heart, but it, too, has serious health effects. It significantly increases the risk of cancers of the mouth and throat, among other health problems.<\/p>\nFigure 13.6.2 Smoking is known to cause many different cancers and chronic diseases.<\/em><\/figcaption><\/figure>\nEven non-smokers may not be spared the deadly risks of tobacco smoke. If you spend time around smokers either at home or on the job, then you are at risk of the dangers of secondhand smoke.\u00a0Secondhand smoke<\/a><\/strong> enters the air directly from burning cigarettes (and cigars and pipes), and indirectly from smokers’ lungs. This smoke may linger in indoor air for hours, and it increases the risk of a wide range of adverse health effects.\u00a0According to Health Canada, second-hand smoke causes 800 deaths from lung cancer and heart disease in non-smokers every year. <\/span>The 2014 U.S. Surgeon General\u2019s Report concluded that there is no established risk-free level of exposure to secondhand smoke. Non-smokers who are exposed to secondhand smoke may have as much as a 30 per cent increase in their risk of lung cancer and heart disease.\u00a0<\/span><\/p>\nTobacco contains\u00a0nicotine<\/a>,<\/strong>\u00a0which is a psychoactive drug. Although nicotine in tobacco smoke does not directly cause cancer<\/a> or most of the other health risks of smoking, it is a highly addictive drug.\u00a0Nicotine is actually even more addictive than cocaine or heroin. The addictive nature of nicotine explains why it is so difficult for smokers to quit the habit, even when they know the health risks and really\u00a0want<\/em>\u00a0to stop smoking. The good news is that if someone\u00a0does<\/em>\u00a0stop smoking, his or her risks of smoking-related diseases and death soon start to fall.\u00a0By one year after quitting, the risk of\u00a0heart\u00a0disease drops to only half of that of a continuing smoker.<\/p>\n\nSmoking and Cancer<\/h1>\n<\/div>\n
One of the main health risks of smoking is cancer, particular cancer of the lung. Because of the increased risk of lung cancer<\/a> with smoking, the risk of dying from lung cancer before age 85 is more than 20 times higher for a male smoker than for a male non-smoker. As the rate of smoking increases, so does the rate of lung cancer deaths, although the effects of smoking on lung cancer deaths can take up to 20 years to manifest themselves, as shown in Figure 13.6.3. Besides lung cancer, several other forms of cancer are also significantly more likely in smokers than non-smokers, including cancers of the kidney, larynx, mouth, lip, tongue, throat, bladder, esophagus, pancreas, and stomach. Unfortunately, many of these cancers have extremely low cure rates.<\/p>\nFigure 13.6.3 Cigarette smoking by men in the U.S. began to decline in the 1950s, but it wasn\u2019t until the 1970s \u2014 roughly 20 years later \u2014 that this was reflected by a concomitant decline in lung cancer deaths in men.<\/em><\/figcaption><\/figure>\nWhen you consider the\u00a0composition\u00a0of tobacco smoke, it\u2019s not surprising that it increases the risk of cancer. Tobacco smoke contains dozens of chemicals proven to be carcinogens, or causes of cancer. Many of these chemicals bind to\u00a0DNA\u00a0in a smoker\u2019s\u00a0cells, and may either kill the cells or cause\u00a0mutations. If the mutations inhibit programmed cell death, the cells can survive to become cancer cells. Some of the most potent carcinogens in tobacco smoke include benzopyrene, acrolein, and nitrosamines. Other carcinogens in tobacco smoke are radioactive isotopes, including lead-210 and polonium-210.<\/p>\n
\nRespiratory Effects of Smoking<\/h1>\n<\/div>\n
Long-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to chronic obstructive pulmonary disease<\/a> (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs’ ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.<\/p>\n\nCardiovascular Effects of Smoking<\/h1>\n<\/div>\n
Inhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of heart attack<\/a> and stroke<\/a>. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.<\/p>\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.<\/p>\n
\nAdditional Adverse Health Effects of Smoking<\/h1>\n<\/div>\n
A wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:<\/p>\n
\n- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\n
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\n
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\n
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\n
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\n
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\n
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\n
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\n<\/ul>\n\n
Feature: Human Biology in the News<\/h1>\n<\/div>\nFigure 13.6.4 An E-Cigarette or Vape.<\/em><\/figcaption><\/figure>\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. E-cigarettes<\/span><\/a><\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span><\/p>\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.<\/p>\n
Some manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers’ attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don’t contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.<\/p>\n\n\n13.6 Summary<\/span><\/h1>\n<\/header>\n\n\n- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The nicotine<\/a> in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\n
- A major health risk of smoking is cancer<\/a> of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as carcinogens<\/a>.<\/li>\n
- Smoking is the primary cause of chronic obstructive pulmonary disease<\/a> (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of alveoli<\/a> so the lungs can no longer fully exhale air.<\/li>\n
- Smoking damages the\u00a0cardiovascular system<\/a>\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, heart attack<\/a>, and stroke<\/a>. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\n
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n\n
\n13.6 Review Questions<\/span><\/h1>\n<\/header>\n\n\n- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\n
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\n
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\n
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\n
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\n
- Explain how smoking causes COPD.<\/li>\n
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\n<\/ol>\n<\/div>\n<\/div>\n\n
\n13.6 Explore More<\/span><\/h1>\n<\/header>\n\n
Cardiovascular Effects of Smoking<\/h1>\r\n<\/div>\r\nInhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of [pb_glossary id=\"4368\"]heart attack[\/pb_glossary] and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.\r\n\r\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.\r\n\r\nAdditional Adverse Health Effects of Smoking<\/h1>\r\n<\/div>\r\nA wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:\r\n\r\n \t- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\r\n \t
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\r\n \t
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\r\n \t
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\r\n \t
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\r\n \t
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\r\n \t
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\r\n \t
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\r\n<\/ul>\r\n\r\n
Feature: Human Biology in the News<\/h1>\r\n<\/div>\r\n\r\n[caption id=\"attachment_4369\" align=\"alignleft\" width=\"382\"] Figure 13.6.4 An E-Cigarette or Vape.<\/em>[\/caption]\r\n\r\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. [pb_glossary id=\"4370\"]E-cigarettes<\/span>[\/pb_glossary]<\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span>\r\n\r\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.\r\n\r\nSome manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers' attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don't contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.\r\n\r\n13.6 Summary<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The [pb_glossary id=\"4366\"]nicotine[\/pb_glossary] in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\r\n \t
- A major health risk of smoking is [pb_glossary id=\"5605\"]cancer[\/pb_glossary] of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as [pb_glossary id=\"4371\"]carcinogens[\/pb_glossary].<\/li>\r\n \t
- Smoking is the primary cause of [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of [pb_glossary id=\"4311\"]alveoli[\/pb_glossary] so the lungs can no longer fully exhale air.<\/li>\r\n \t
- Smoking damages the\u00a0[pb_glossary id=\"5927\"]cardiovascular system[\/pb_glossary]\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, [pb_glossary id=\"4368\"]heart attack[\/pb_glossary], and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\r\n \t
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Review Questions<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\r\n \t
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\r\n \t
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\r\n \t
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\r\n \t
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\r\n \t
- Explain how smoking causes COPD.<\/li>\r\n \t
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\r\n<\/ol>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Explore More<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\nhttps:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=emb_logo\r\nBlowing Smoke: The Lost Legacy of the Surgeon General's Report | Alan Blum | TEDxTuscaloosa, TEDx Talks, 2015.<\/p>\r\nhttps:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU\r\n
The dangers of vaping, RWJ Barnabas Health, 2019.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n \r\n
Attributions<\/h2>\r\nFigure 13.6.1<\/strong>\r\n\r\n\r\n\r\n\r\nCigarette<\/a>\u00a0by \u00a0Uitbundig<\/a>\u00a0on\u00a0Unsplash<\/a>\u00a0is used under the\u00a0Unsplash License<\/a>\u00a0(https:\/\/unsplash.com\/license<\/a>)\r\n\r\nFigure 13.6.2<\/strong>\r\n\r\nRisks_from_smoking-smoking_can_damage_every_part_of_the_body<\/a> by CDC<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.3<\/strong>\r\n\r\nCancer_smoking_lung_cancer_correlation_from_NIH.svg<\/a> by Sakurambo<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.4<\/strong>\r\n\r\nAn_Electronic_Cigarette_(11359245033)<\/a> by Lindsay Fox<\/a> from Newport beach, United States on Wikimedia Commons is used under a\u00a0CC BY 2.0<\/a> (https:\/\/creativecommons.org\/licenses\/by\/2.0) license.\r\n\r\n<\/div>\r\n<\/section>\r\nReferences<\/h2>\r\n
Allen, J. G., Flanigan, S. S., LeBlanc, M., Vallarino, J., MacNaughton, P., Stewart, J. H., Christiani, D.C. (2016, June 1). Flavoring chemicals in E-Cigarettes: Diacetyl, 2,3-Pentanedione, and Acetoin in a sample of 51 products, including fruit-, candy-, and cocktail-flavored E-cigarettes [online article]. Environmental Health Perspectives, 124:733\u2013739. <\/em>https:\/\/doi.org\/10.1289\/ehp.1510185<\/span><\/p>\r\nHealth Canada. (2015). Dangers of second-hand smoke [online article]. Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/smoking-tobacco\/avoid-second-hand-smoke\/second-hand-smoke\/dangers-second-hand-smoke.html<\/p>\r\n
RWJ Barnabas Health. (2019, September 25). The dangers of vaping. YouTube. https:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU&feature=youtu.be<\/p>\r\n
TEDx Talks. (2015, August 7). Blowing smoke: The lost legacy of the surgeon general's report | Alan Blum | TEDxTuscaloosa. https:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=youtu.be<\/p>\r\n
Tobacco and Vaping Products Act. (2016, June 26). Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/health-concerns\/tobacco\/legislation\/federal-laws\/tobacco-act.html<\/p>\r\n
Vaping, E-cigarettes to be regulated by Health Canada. (2016, November 22). CBC\/Radio-Canada. HTTP:\/\/www.cbc.ca\/news\/health\/vaping-health-canada-legislation-1.3862589<\/cite><\/span><\/p>\r\nWikipedia contributors. (2020, August 9). Regulation of electronic cigarettes. In\u00a0Wikipedia. <\/i>\u00a0https:\/\/en.wikipedia.org\/w\/index.php?title=Regulation_of_electronic_cigarettes&oldid=972059825<\/p>\r\n
<\/p>","rendered":"
<\/p>\nFigure 13.6.1 Smoking kills.<\/em><\/figcaption><\/figure>\n\nSure Death<\/h1>\n<\/div>\n
This anti-smoking photo (Figure 13.6.1) clearly makes the point that smoking causes death. The image is not using hyperbole, because smoking actually is<\/em> deadly. It causes about\u00a07\u00a0million deaths each year, and is the single greatest cause of preventable death worldwide. As many as half of all people who smoke tobacco die from it. As a result of smoking\u2019s deadly effects, the life expectancy of long-term smokers is significantly less than that of non-smokers. In fact, long-term smokers can expect their lifespan to be reduced by as much as 18 years, and they are three times\u00a0more\u00a0likely than non-smokers to die before the age of 70.<\/p>\n\nWhy Is Smoking Deadly?<\/h1>\n<\/div>\n
As shown in Figure 13.6.2, tobacco smoking has adverse effects on just about every bodily system and organ. The detrimental health effects of smoking depend on the number of years that a person smokes and how much the person smokes. Contrary to popular belief, all forms of tobacco smoke \u2014 including smoke from cigars and tobacco pipes \u2014 have similar health risks as those of cigarette smoke. Smokeless tobacco may be less of a danger to the lungs and heart, but it, too, has serious health effects. It significantly increases the risk of cancers of the mouth and throat, among other health problems.<\/p>\nFigure 13.6.2 Smoking is known to cause many different cancers and chronic diseases.<\/em><\/figcaption><\/figure>\nEven non-smokers may not be spared the deadly risks of tobacco smoke. If you spend time around smokers either at home or on the job, then you are at risk of the dangers of secondhand smoke.\u00a0Secondhand smoke<\/a><\/strong> enters the air directly from burning cigarettes (and cigars and pipes), and indirectly from smokers’ lungs. This smoke may linger in indoor air for hours, and it increases the risk of a wide range of adverse health effects.\u00a0According to Health Canada, second-hand smoke causes 800 deaths from lung cancer and heart disease in non-smokers every year. <\/span>The 2014 U.S. Surgeon General\u2019s Report concluded that there is no established risk-free level of exposure to secondhand smoke. Non-smokers who are exposed to secondhand smoke may have as much as a 30 per cent increase in their risk of lung cancer and heart disease.\u00a0<\/span><\/p>\nTobacco contains\u00a0nicotine<\/a>,<\/strong>\u00a0which is a psychoactive drug. Although nicotine in tobacco smoke does not directly cause cancer<\/a> or most of the other health risks of smoking, it is a highly addictive drug.\u00a0Nicotine is actually even more addictive than cocaine or heroin. The addictive nature of nicotine explains why it is so difficult for smokers to quit the habit, even when they know the health risks and really\u00a0want<\/em>\u00a0to stop smoking. The good news is that if someone\u00a0does<\/em>\u00a0stop smoking, his or her risks of smoking-related diseases and death soon start to fall.\u00a0By one year after quitting, the risk of\u00a0heart\u00a0disease drops to only half of that of a continuing smoker.<\/p>\n\nSmoking and Cancer<\/h1>\n<\/div>\n
One of the main health risks of smoking is cancer, particular cancer of the lung. Because of the increased risk of lung cancer<\/a> with smoking, the risk of dying from lung cancer before age 85 is more than 20 times higher for a male smoker than for a male non-smoker. As the rate of smoking increases, so does the rate of lung cancer deaths, although the effects of smoking on lung cancer deaths can take up to 20 years to manifest themselves, as shown in Figure 13.6.3. Besides lung cancer, several other forms of cancer are also significantly more likely in smokers than non-smokers, including cancers of the kidney, larynx, mouth, lip, tongue, throat, bladder, esophagus, pancreas, and stomach. Unfortunately, many of these cancers have extremely low cure rates.<\/p>\nFigure 13.6.3 Cigarette smoking by men in the U.S. began to decline in the 1950s, but it wasn\u2019t until the 1970s \u2014 roughly 20 years later \u2014 that this was reflected by a concomitant decline in lung cancer deaths in men.<\/em><\/figcaption><\/figure>\nWhen you consider the\u00a0composition\u00a0of tobacco smoke, it\u2019s not surprising that it increases the risk of cancer. Tobacco smoke contains dozens of chemicals proven to be carcinogens, or causes of cancer. Many of these chemicals bind to\u00a0DNA\u00a0in a smoker\u2019s\u00a0cells, and may either kill the cells or cause\u00a0mutations. If the mutations inhibit programmed cell death, the cells can survive to become cancer cells. Some of the most potent carcinogens in tobacco smoke include benzopyrene, acrolein, and nitrosamines. Other carcinogens in tobacco smoke are radioactive isotopes, including lead-210 and polonium-210.<\/p>\n
\nRespiratory Effects of Smoking<\/h1>\n<\/div>\n
Long-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to chronic obstructive pulmonary disease<\/a> (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs’ ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.<\/p>\n\nCardiovascular Effects of Smoking<\/h1>\n<\/div>\n
Inhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of heart attack<\/a> and stroke<\/a>. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.<\/p>\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.<\/p>\n
\nAdditional Adverse Health Effects of Smoking<\/h1>\n<\/div>\n
A wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:<\/p>\n
\n- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\n
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\n
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\n
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\n
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\n
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\n
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\n
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\n<\/ul>\n\n
Feature: Human Biology in the News<\/h1>\n<\/div>\nFigure 13.6.4 An E-Cigarette or Vape.<\/em><\/figcaption><\/figure>\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. E-cigarettes<\/span><\/a><\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span><\/p>\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.<\/p>\n
Some manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers’ attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don’t contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.<\/p>\n\n\n13.6 Summary<\/span><\/h1>\n<\/header>\n\n\n- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The nicotine<\/a> in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\n
- A major health risk of smoking is cancer<\/a> of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as carcinogens<\/a>.<\/li>\n
- Smoking is the primary cause of chronic obstructive pulmonary disease<\/a> (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of alveoli<\/a> so the lungs can no longer fully exhale air.<\/li>\n
- Smoking damages the\u00a0cardiovascular system<\/a>\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, heart attack<\/a>, and stroke<\/a>. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\n
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n\n
\n13.6 Review Questions<\/span><\/h1>\n<\/header>\n\n\n- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\n
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\n
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\n
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\n
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\n
- Explain how smoking causes COPD.<\/li>\n
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\n<\/ol>\n<\/div>\n<\/div>\n\n
\n13.6 Explore More<\/span><\/h1>\n<\/header>\n\n
Additional Adverse Health Effects of Smoking<\/h1>\r\n<\/div>\r\nA wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:\r\n\r\n \t- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\r\n \t
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\r\n \t
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\r\n \t
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\r\n \t
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\r\n \t
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\r\n \t
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\r\n \t
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\r\n<\/ul>\r\n\r\n
Feature: Human Biology in the News<\/h1>\r\n<\/div>\r\n\r\n[caption id=\"attachment_4369\" align=\"alignleft\" width=\"382\"] Figure 13.6.4 An E-Cigarette or Vape.<\/em>[\/caption]\r\n\r\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. [pb_glossary id=\"4370\"]E-cigarettes<\/span>[\/pb_glossary]<\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span>\r\n\r\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.\r\n\r\nSome manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers' attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don't contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.\r\n\r\n13.6 Summary<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The [pb_glossary id=\"4366\"]nicotine[\/pb_glossary] in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\r\n \t
- A major health risk of smoking is [pb_glossary id=\"5605\"]cancer[\/pb_glossary] of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as [pb_glossary id=\"4371\"]carcinogens[\/pb_glossary].<\/li>\r\n \t
- Smoking is the primary cause of [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of [pb_glossary id=\"4311\"]alveoli[\/pb_glossary] so the lungs can no longer fully exhale air.<\/li>\r\n \t
- Smoking damages the\u00a0[pb_glossary id=\"5927\"]cardiovascular system[\/pb_glossary]\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, [pb_glossary id=\"4368\"]heart attack[\/pb_glossary], and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\r\n \t
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Review Questions<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\r\n \t
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\r\n \t
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\r\n \t
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\r\n \t
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\r\n \t
- Explain how smoking causes COPD.<\/li>\r\n \t
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\r\n<\/ol>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Explore More<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\nhttps:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=emb_logo\r\nBlowing Smoke: The Lost Legacy of the Surgeon General's Report | Alan Blum | TEDxTuscaloosa, TEDx Talks, 2015.<\/p>\r\nhttps:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU\r\n
The dangers of vaping, RWJ Barnabas Health, 2019.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n \r\n
Attributions<\/h2>\r\nFigure 13.6.1<\/strong>\r\n\r\n\r\n\r\n\r\nCigarette<\/a>\u00a0by \u00a0Uitbundig<\/a>\u00a0on\u00a0Unsplash<\/a>\u00a0is used under the\u00a0Unsplash License<\/a>\u00a0(https:\/\/unsplash.com\/license<\/a>)\r\n\r\nFigure 13.6.2<\/strong>\r\n\r\nRisks_from_smoking-smoking_can_damage_every_part_of_the_body<\/a> by CDC<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.3<\/strong>\r\n\r\nCancer_smoking_lung_cancer_correlation_from_NIH.svg<\/a> by Sakurambo<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.4<\/strong>\r\n\r\nAn_Electronic_Cigarette_(11359245033)<\/a> by Lindsay Fox<\/a> from Newport beach, United States on Wikimedia Commons is used under a\u00a0CC BY 2.0<\/a> (https:\/\/creativecommons.org\/licenses\/by\/2.0) license.\r\n\r\n<\/div>\r\n<\/section>\r\nReferences<\/h2>\r\n
Allen, J. G., Flanigan, S. S., LeBlanc, M., Vallarino, J., MacNaughton, P., Stewart, J. H., Christiani, D.C. (2016, June 1). Flavoring chemicals in E-Cigarettes: Diacetyl, 2,3-Pentanedione, and Acetoin in a sample of 51 products, including fruit-, candy-, and cocktail-flavored E-cigarettes [online article]. Environmental Health Perspectives, 124:733\u2013739. <\/em>https:\/\/doi.org\/10.1289\/ehp.1510185<\/span><\/p>\r\nHealth Canada. (2015). Dangers of second-hand smoke [online article]. Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/smoking-tobacco\/avoid-second-hand-smoke\/second-hand-smoke\/dangers-second-hand-smoke.html<\/p>\r\n
RWJ Barnabas Health. (2019, September 25). The dangers of vaping. YouTube. https:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU&feature=youtu.be<\/p>\r\n
TEDx Talks. (2015, August 7). Blowing smoke: The lost legacy of the surgeon general's report | Alan Blum | TEDxTuscaloosa. https:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=youtu.be<\/p>\r\n
Tobacco and Vaping Products Act. (2016, June 26). Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/health-concerns\/tobacco\/legislation\/federal-laws\/tobacco-act.html<\/p>\r\n
Vaping, E-cigarettes to be regulated by Health Canada. (2016, November 22). CBC\/Radio-Canada. HTTP:\/\/www.cbc.ca\/news\/health\/vaping-health-canada-legislation-1.3862589<\/cite><\/span><\/p>\r\nWikipedia contributors. (2020, August 9). Regulation of electronic cigarettes. In\u00a0Wikipedia. <\/i>\u00a0https:\/\/en.wikipedia.org\/w\/index.php?title=Regulation_of_electronic_cigarettes&oldid=972059825<\/p>\r\n
<\/p>","rendered":"
<\/p>\nFigure 13.6.1 Smoking kills.<\/em><\/figcaption><\/figure>\n\nSure Death<\/h1>\n<\/div>\n
This anti-smoking photo (Figure 13.6.1) clearly makes the point that smoking causes death. The image is not using hyperbole, because smoking actually is<\/em> deadly. It causes about\u00a07\u00a0million deaths each year, and is the single greatest cause of preventable death worldwide. As many as half of all people who smoke tobacco die from it. As a result of smoking\u2019s deadly effects, the life expectancy of long-term smokers is significantly less than that of non-smokers. In fact, long-term smokers can expect their lifespan to be reduced by as much as 18 years, and they are three times\u00a0more\u00a0likely than non-smokers to die before the age of 70.<\/p>\n\nWhy Is Smoking Deadly?<\/h1>\n<\/div>\n
As shown in Figure 13.6.2, tobacco smoking has adverse effects on just about every bodily system and organ. The detrimental health effects of smoking depend on the number of years that a person smokes and how much the person smokes. Contrary to popular belief, all forms of tobacco smoke \u2014 including smoke from cigars and tobacco pipes \u2014 have similar health risks as those of cigarette smoke. Smokeless tobacco may be less of a danger to the lungs and heart, but it, too, has serious health effects. It significantly increases the risk of cancers of the mouth and throat, among other health problems.<\/p>\nFigure 13.6.2 Smoking is known to cause many different cancers and chronic diseases.<\/em><\/figcaption><\/figure>\nEven non-smokers may not be spared the deadly risks of tobacco smoke. If you spend time around smokers either at home or on the job, then you are at risk of the dangers of secondhand smoke.\u00a0Secondhand smoke<\/a><\/strong> enters the air directly from burning cigarettes (and cigars and pipes), and indirectly from smokers’ lungs. This smoke may linger in indoor air for hours, and it increases the risk of a wide range of adverse health effects.\u00a0According to Health Canada, second-hand smoke causes 800 deaths from lung cancer and heart disease in non-smokers every year. <\/span>The 2014 U.S. Surgeon General\u2019s Report concluded that there is no established risk-free level of exposure to secondhand smoke. Non-smokers who are exposed to secondhand smoke may have as much as a 30 per cent increase in their risk of lung cancer and heart disease.\u00a0<\/span><\/p>\nTobacco contains\u00a0nicotine<\/a>,<\/strong>\u00a0which is a psychoactive drug. Although nicotine in tobacco smoke does not directly cause cancer<\/a> or most of the other health risks of smoking, it is a highly addictive drug.\u00a0Nicotine is actually even more addictive than cocaine or heroin. The addictive nature of nicotine explains why it is so difficult for smokers to quit the habit, even when they know the health risks and really\u00a0want<\/em>\u00a0to stop smoking. The good news is that if someone\u00a0does<\/em>\u00a0stop smoking, his or her risks of smoking-related diseases and death soon start to fall.\u00a0By one year after quitting, the risk of\u00a0heart\u00a0disease drops to only half of that of a continuing smoker.<\/p>\n\nSmoking and Cancer<\/h1>\n<\/div>\n
One of the main health risks of smoking is cancer, particular cancer of the lung. Because of the increased risk of lung cancer<\/a> with smoking, the risk of dying from lung cancer before age 85 is more than 20 times higher for a male smoker than for a male non-smoker. As the rate of smoking increases, so does the rate of lung cancer deaths, although the effects of smoking on lung cancer deaths can take up to 20 years to manifest themselves, as shown in Figure 13.6.3. Besides lung cancer, several other forms of cancer are also significantly more likely in smokers than non-smokers, including cancers of the kidney, larynx, mouth, lip, tongue, throat, bladder, esophagus, pancreas, and stomach. Unfortunately, many of these cancers have extremely low cure rates.<\/p>\nFigure 13.6.3 Cigarette smoking by men in the U.S. began to decline in the 1950s, but it wasn\u2019t until the 1970s \u2014 roughly 20 years later \u2014 that this was reflected by a concomitant decline in lung cancer deaths in men.<\/em><\/figcaption><\/figure>\nWhen you consider the\u00a0composition\u00a0of tobacco smoke, it\u2019s not surprising that it increases the risk of cancer. Tobacco smoke contains dozens of chemicals proven to be carcinogens, or causes of cancer. Many of these chemicals bind to\u00a0DNA\u00a0in a smoker\u2019s\u00a0cells, and may either kill the cells or cause\u00a0mutations. If the mutations inhibit programmed cell death, the cells can survive to become cancer cells. Some of the most potent carcinogens in tobacco smoke include benzopyrene, acrolein, and nitrosamines. Other carcinogens in tobacco smoke are radioactive isotopes, including lead-210 and polonium-210.<\/p>\n
\nRespiratory Effects of Smoking<\/h1>\n<\/div>\n
Long-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to chronic obstructive pulmonary disease<\/a> (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs’ ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.<\/p>\n\nCardiovascular Effects of Smoking<\/h1>\n<\/div>\n
Inhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of heart attack<\/a> and stroke<\/a>. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.<\/p>\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.<\/p>\n
\nAdditional Adverse Health Effects of Smoking<\/h1>\n<\/div>\n
A wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:<\/p>\n
\n- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\n
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\n
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\n
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\n
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\n
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\n
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\n
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\n<\/ul>\n\n
Feature: Human Biology in the News<\/h1>\n<\/div>\nFigure 13.6.4 An E-Cigarette or Vape.<\/em><\/figcaption><\/figure>\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. E-cigarettes<\/span><\/a><\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span><\/p>\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.<\/p>\n
Some manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers’ attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don’t contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.<\/p>\n\n\n13.6 Summary<\/span><\/h1>\n<\/header>\n\n\n- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The nicotine<\/a> in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\n
- A major health risk of smoking is cancer<\/a> of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as carcinogens<\/a>.<\/li>\n
- Smoking is the primary cause of chronic obstructive pulmonary disease<\/a> (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of alveoli<\/a> so the lungs can no longer fully exhale air.<\/li>\n
- Smoking damages the\u00a0cardiovascular system<\/a>\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, heart attack<\/a>, and stroke<\/a>. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\n
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n\n
\n13.6 Review Questions<\/span><\/h1>\n<\/header>\n\n\n- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\n
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\n
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\n
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\n
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\n
- Explain how smoking causes COPD.<\/li>\n
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\n<\/ol>\n<\/div>\n<\/div>\n\n
\n13.6 Explore More<\/span><\/h1>\n<\/header>\n\n
Feature: Human Biology in the News<\/h1>\r\n<\/div>\r\n\r\n[caption id=\"attachment_4369\" align=\"alignleft\" width=\"382\"] Figure 13.6.4 An E-Cigarette or Vape.<\/em>[\/caption]\r\n\r\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. [pb_glossary id=\"4370\"]E-cigarettes<\/span>[\/pb_glossary]<\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span>\r\n\r\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.\r\n\r\nSome manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers' attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don't contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.\r\n\r\n13.6 Summary<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The [pb_glossary id=\"4366\"]nicotine[\/pb_glossary] in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\r\n \t
- A major health risk of smoking is [pb_glossary id=\"5605\"]cancer[\/pb_glossary] of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as [pb_glossary id=\"4371\"]carcinogens[\/pb_glossary].<\/li>\r\n \t
- Smoking is the primary cause of [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of [pb_glossary id=\"4311\"]alveoli[\/pb_glossary] so the lungs can no longer fully exhale air.<\/li>\r\n \t
- Smoking damages the\u00a0[pb_glossary id=\"5927\"]cardiovascular system[\/pb_glossary]\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, [pb_glossary id=\"4368\"]heart attack[\/pb_glossary], and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\r\n \t
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Review Questions<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\r\n \t
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\r\n \t
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\r\n \t
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\r\n \t
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\r\n \t
- Explain how smoking causes COPD.<\/li>\r\n \t
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\r\n<\/ol>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Explore More<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\nhttps:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=emb_logo\r\nBlowing Smoke: The Lost Legacy of the Surgeon General's Report | Alan Blum | TEDxTuscaloosa, TEDx Talks, 2015.<\/p>\r\nhttps:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU\r\n
The dangers of vaping, RWJ Barnabas Health, 2019.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n \r\n
Attributions<\/h2>\r\nFigure 13.6.1<\/strong>\r\n\r\n\r\n\r\n\r\nCigarette<\/a>\u00a0by \u00a0Uitbundig<\/a>\u00a0on\u00a0Unsplash<\/a>\u00a0is used under the\u00a0Unsplash License<\/a>\u00a0(https:\/\/unsplash.com\/license<\/a>)\r\n\r\nFigure 13.6.2<\/strong>\r\n\r\nRisks_from_smoking-smoking_can_damage_every_part_of_the_body<\/a> by CDC<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.3<\/strong>\r\n\r\nCancer_smoking_lung_cancer_correlation_from_NIH.svg<\/a> by Sakurambo<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.4<\/strong>\r\n\r\nAn_Electronic_Cigarette_(11359245033)<\/a> by Lindsay Fox<\/a> from Newport beach, United States on Wikimedia Commons is used under a\u00a0CC BY 2.0<\/a> (https:\/\/creativecommons.org\/licenses\/by\/2.0) license.\r\n\r\n<\/div>\r\n<\/section>\r\nReferences<\/h2>\r\n
Allen, J. G., Flanigan, S. S., LeBlanc, M., Vallarino, J., MacNaughton, P., Stewart, J. H., Christiani, D.C. (2016, June 1). Flavoring chemicals in E-Cigarettes: Diacetyl, 2,3-Pentanedione, and Acetoin in a sample of 51 products, including fruit-, candy-, and cocktail-flavored E-cigarettes [online article]. Environmental Health Perspectives, 124:733\u2013739. <\/em>https:\/\/doi.org\/10.1289\/ehp.1510185<\/span><\/p>\r\nHealth Canada. (2015). Dangers of second-hand smoke [online article]. Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/smoking-tobacco\/avoid-second-hand-smoke\/second-hand-smoke\/dangers-second-hand-smoke.html<\/p>\r\n
RWJ Barnabas Health. (2019, September 25). The dangers of vaping. YouTube. https:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU&feature=youtu.be<\/p>\r\n
TEDx Talks. (2015, August 7). Blowing smoke: The lost legacy of the surgeon general's report | Alan Blum | TEDxTuscaloosa. https:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=youtu.be<\/p>\r\n
Tobacco and Vaping Products Act. (2016, June 26). Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/health-concerns\/tobacco\/legislation\/federal-laws\/tobacco-act.html<\/p>\r\n
Vaping, E-cigarettes to be regulated by Health Canada. (2016, November 22). CBC\/Radio-Canada. HTTP:\/\/www.cbc.ca\/news\/health\/vaping-health-canada-legislation-1.3862589<\/cite><\/span><\/p>\r\nWikipedia contributors. (2020, August 9). Regulation of electronic cigarettes. In\u00a0Wikipedia. <\/i>\u00a0https:\/\/en.wikipedia.org\/w\/index.php?title=Regulation_of_electronic_cigarettes&oldid=972059825<\/p>\r\n
<\/p>","rendered":"
<\/p>\nFigure 13.6.1 Smoking kills.<\/em><\/figcaption><\/figure>\n\nSure Death<\/h1>\n<\/div>\n
This anti-smoking photo (Figure 13.6.1) clearly makes the point that smoking causes death. The image is not using hyperbole, because smoking actually is<\/em> deadly. It causes about\u00a07\u00a0million deaths each year, and is the single greatest cause of preventable death worldwide. As many as half of all people who smoke tobacco die from it. As a result of smoking\u2019s deadly effects, the life expectancy of long-term smokers is significantly less than that of non-smokers. In fact, long-term smokers can expect their lifespan to be reduced by as much as 18 years, and they are three times\u00a0more\u00a0likely than non-smokers to die before the age of 70.<\/p>\n\nWhy Is Smoking Deadly?<\/h1>\n<\/div>\n
As shown in Figure 13.6.2, tobacco smoking has adverse effects on just about every bodily system and organ. The detrimental health effects of smoking depend on the number of years that a person smokes and how much the person smokes. Contrary to popular belief, all forms of tobacco smoke \u2014 including smoke from cigars and tobacco pipes \u2014 have similar health risks as those of cigarette smoke. Smokeless tobacco may be less of a danger to the lungs and heart, but it, too, has serious health effects. It significantly increases the risk of cancers of the mouth and throat, among other health problems.<\/p>\nFigure 13.6.2 Smoking is known to cause many different cancers and chronic diseases.<\/em><\/figcaption><\/figure>\nEven non-smokers may not be spared the deadly risks of tobacco smoke. If you spend time around smokers either at home or on the job, then you are at risk of the dangers of secondhand smoke.\u00a0Secondhand smoke<\/a><\/strong> enters the air directly from burning cigarettes (and cigars and pipes), and indirectly from smokers’ lungs. This smoke may linger in indoor air for hours, and it increases the risk of a wide range of adverse health effects.\u00a0According to Health Canada, second-hand smoke causes 800 deaths from lung cancer and heart disease in non-smokers every year. <\/span>The 2014 U.S. Surgeon General\u2019s Report concluded that there is no established risk-free level of exposure to secondhand smoke. Non-smokers who are exposed to secondhand smoke may have as much as a 30 per cent increase in their risk of lung cancer and heart disease.\u00a0<\/span><\/p>\nTobacco contains\u00a0nicotine<\/a>,<\/strong>\u00a0which is a psychoactive drug. Although nicotine in tobacco smoke does not directly cause cancer<\/a> or most of the other health risks of smoking, it is a highly addictive drug.\u00a0Nicotine is actually even more addictive than cocaine or heroin. The addictive nature of nicotine explains why it is so difficult for smokers to quit the habit, even when they know the health risks and really\u00a0want<\/em>\u00a0to stop smoking. The good news is that if someone\u00a0does<\/em>\u00a0stop smoking, his or her risks of smoking-related diseases and death soon start to fall.\u00a0By one year after quitting, the risk of\u00a0heart\u00a0disease drops to only half of that of a continuing smoker.<\/p>\n\nSmoking and Cancer<\/h1>\n<\/div>\n
One of the main health risks of smoking is cancer, particular cancer of the lung. Because of the increased risk of lung cancer<\/a> with smoking, the risk of dying from lung cancer before age 85 is more than 20 times higher for a male smoker than for a male non-smoker. As the rate of smoking increases, so does the rate of lung cancer deaths, although the effects of smoking on lung cancer deaths can take up to 20 years to manifest themselves, as shown in Figure 13.6.3. Besides lung cancer, several other forms of cancer are also significantly more likely in smokers than non-smokers, including cancers of the kidney, larynx, mouth, lip, tongue, throat, bladder, esophagus, pancreas, and stomach. Unfortunately, many of these cancers have extremely low cure rates.<\/p>\nFigure 13.6.3 Cigarette smoking by men in the U.S. began to decline in the 1950s, but it wasn\u2019t until the 1970s \u2014 roughly 20 years later \u2014 that this was reflected by a concomitant decline in lung cancer deaths in men.<\/em><\/figcaption><\/figure>\nWhen you consider the\u00a0composition\u00a0of tobacco smoke, it\u2019s not surprising that it increases the risk of cancer. Tobacco smoke contains dozens of chemicals proven to be carcinogens, or causes of cancer. Many of these chemicals bind to\u00a0DNA\u00a0in a smoker\u2019s\u00a0cells, and may either kill the cells or cause\u00a0mutations. If the mutations inhibit programmed cell death, the cells can survive to become cancer cells. Some of the most potent carcinogens in tobacco smoke include benzopyrene, acrolein, and nitrosamines. Other carcinogens in tobacco smoke are radioactive isotopes, including lead-210 and polonium-210.<\/p>\n
\nRespiratory Effects of Smoking<\/h1>\n<\/div>\n
Long-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to chronic obstructive pulmonary disease<\/a> (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs’ ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.<\/p>\n\nCardiovascular Effects of Smoking<\/h1>\n<\/div>\n
Inhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of heart attack<\/a> and stroke<\/a>. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.<\/p>\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.<\/p>\n
\nAdditional Adverse Health Effects of Smoking<\/h1>\n<\/div>\n
A wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:<\/p>\n
\n- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\n
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\n
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\n
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\n
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\n
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\n
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\n
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\n<\/ul>\n\n
Feature: Human Biology in the News<\/h1>\n<\/div>\nFigure 13.6.4 An E-Cigarette or Vape.<\/em><\/figcaption><\/figure>\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. E-cigarettes<\/span><\/a><\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span><\/p>\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.<\/p>\n
Some manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers’ attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don’t contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.<\/p>\n\n\n13.6 Summary<\/span><\/h1>\n<\/header>\n\n\n- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The nicotine<\/a> in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\n
- A major health risk of smoking is cancer<\/a> of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as carcinogens<\/a>.<\/li>\n
- Smoking is the primary cause of chronic obstructive pulmonary disease<\/a> (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of alveoli<\/a> so the lungs can no longer fully exhale air.<\/li>\n
- Smoking damages the\u00a0cardiovascular system<\/a>\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, heart attack<\/a>, and stroke<\/a>. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\n
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n\n
\n13.6 Review Questions<\/span><\/h1>\n<\/header>\n\n\n- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\n
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\n
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\n
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\n
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\n
- Explain how smoking causes COPD.<\/li>\n
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\n<\/ol>\n<\/div>\n<\/div>\n\n
\n13.6 Explore More<\/span><\/h1>\n<\/header>\n\n
13.6 Summary<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The [pb_glossary id=\"4366\"]nicotine[\/pb_glossary] in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\r\n \t
- A major health risk of smoking is [pb_glossary id=\"5605\"]cancer[\/pb_glossary] of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as [pb_glossary id=\"4371\"]carcinogens[\/pb_glossary].<\/li>\r\n \t
- Smoking is the primary cause of [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of [pb_glossary id=\"4311\"]alveoli[\/pb_glossary] so the lungs can no longer fully exhale air.<\/li>\r\n \t
- Smoking damages the\u00a0[pb_glossary id=\"5927\"]cardiovascular system[\/pb_glossary]\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, [pb_glossary id=\"4368\"]heart attack[\/pb_glossary], and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\r\n \t
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Review Questions<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\n \t- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\r\n \t
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\r\n \t
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\r\n \t
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\r\n \t
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\r\n \t
- Explain how smoking causes COPD.<\/li>\r\n \t
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\r\n<\/ol>\r\n<\/div>\r\n<\/div>\r\n
\r\n13.6 Explore More<\/span><\/h1>\r\n<\/header>\r\n\r\n\r\nhttps:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=emb_logo\r\nBlowing Smoke: The Lost Legacy of the Surgeon General's Report | Alan Blum | TEDxTuscaloosa, TEDx Talks, 2015.<\/p>\r\nhttps:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU\r\n
The dangers of vaping, RWJ Barnabas Health, 2019.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n \r\n
Attributions<\/h2>\r\nFigure 13.6.1<\/strong>\r\n\r\n\r\n\r\n\r\nCigarette<\/a>\u00a0by \u00a0Uitbundig<\/a>\u00a0on\u00a0Unsplash<\/a>\u00a0is used under the\u00a0Unsplash License<\/a>\u00a0(https:\/\/unsplash.com\/license<\/a>)\r\n\r\nFigure 13.6.2<\/strong>\r\n\r\nRisks_from_smoking-smoking_can_damage_every_part_of_the_body<\/a> by CDC<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.3<\/strong>\r\n\r\nCancer_smoking_lung_cancer_correlation_from_NIH.svg<\/a> by Sakurambo<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.4<\/strong>\r\n\r\nAn_Electronic_Cigarette_(11359245033)<\/a> by Lindsay Fox<\/a> from Newport beach, United States on Wikimedia Commons is used under a\u00a0CC BY 2.0<\/a> (https:\/\/creativecommons.org\/licenses\/by\/2.0) license.\r\n\r\n<\/div>\r\n<\/section>\r\nReferences<\/h2>\r\n
Allen, J. G., Flanigan, S. S., LeBlanc, M., Vallarino, J., MacNaughton, P., Stewart, J. H., Christiani, D.C. (2016, June 1). Flavoring chemicals in E-Cigarettes: Diacetyl, 2,3-Pentanedione, and Acetoin in a sample of 51 products, including fruit-, candy-, and cocktail-flavored E-cigarettes [online article]. Environmental Health Perspectives, 124:733\u2013739. <\/em>https:\/\/doi.org\/10.1289\/ehp.1510185<\/span><\/p>\r\nHealth Canada. (2015). Dangers of second-hand smoke [online article]. Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/smoking-tobacco\/avoid-second-hand-smoke\/second-hand-smoke\/dangers-second-hand-smoke.html<\/p>\r\n
RWJ Barnabas Health. (2019, September 25). The dangers of vaping. YouTube. https:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU&feature=youtu.be<\/p>\r\n
TEDx Talks. (2015, August 7). Blowing smoke: The lost legacy of the surgeon general's report | Alan Blum | TEDxTuscaloosa. https:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=youtu.be<\/p>\r\n
Tobacco and Vaping Products Act. (2016, June 26). Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/health-concerns\/tobacco\/legislation\/federal-laws\/tobacco-act.html<\/p>\r\n
Vaping, E-cigarettes to be regulated by Health Canada. (2016, November 22). CBC\/Radio-Canada. HTTP:\/\/www.cbc.ca\/news\/health\/vaping-health-canada-legislation-1.3862589<\/cite><\/span><\/p>\r\nWikipedia contributors. (2020, August 9). Regulation of electronic cigarettes. In\u00a0Wikipedia. <\/i>\u00a0https:\/\/en.wikipedia.org\/w\/index.php?title=Regulation_of_electronic_cigarettes&oldid=972059825<\/p>\r\n
<\/p>","rendered":"
<\/p>\nFigure 13.6.1 Smoking kills.<\/em><\/figcaption><\/figure>\n\nSure Death<\/h1>\n<\/div>\n
This anti-smoking photo (Figure 13.6.1) clearly makes the point that smoking causes death. The image is not using hyperbole, because smoking actually is<\/em> deadly. It causes about\u00a07\u00a0million deaths each year, and is the single greatest cause of preventable death worldwide. As many as half of all people who smoke tobacco die from it. As a result of smoking\u2019s deadly effects, the life expectancy of long-term smokers is significantly less than that of non-smokers. In fact, long-term smokers can expect their lifespan to be reduced by as much as 18 years, and they are three times\u00a0more\u00a0likely than non-smokers to die before the age of 70.<\/p>\n\nWhy Is Smoking Deadly?<\/h1>\n<\/div>\n
As shown in Figure 13.6.2, tobacco smoking has adverse effects on just about every bodily system and organ. The detrimental health effects of smoking depend on the number of years that a person smokes and how much the person smokes. Contrary to popular belief, all forms of tobacco smoke \u2014 including smoke from cigars and tobacco pipes \u2014 have similar health risks as those of cigarette smoke. Smokeless tobacco may be less of a danger to the lungs and heart, but it, too, has serious health effects. It significantly increases the risk of cancers of the mouth and throat, among other health problems.<\/p>\nFigure 13.6.2 Smoking is known to cause many different cancers and chronic diseases.<\/em><\/figcaption><\/figure>\nEven non-smokers may not be spared the deadly risks of tobacco smoke. If you spend time around smokers either at home or on the job, then you are at risk of the dangers of secondhand smoke.\u00a0Secondhand smoke<\/a><\/strong> enters the air directly from burning cigarettes (and cigars and pipes), and indirectly from smokers’ lungs. This smoke may linger in indoor air for hours, and it increases the risk of a wide range of adverse health effects.\u00a0According to Health Canada, second-hand smoke causes 800 deaths from lung cancer and heart disease in non-smokers every year. <\/span>The 2014 U.S. Surgeon General\u2019s Report concluded that there is no established risk-free level of exposure to secondhand smoke. Non-smokers who are exposed to secondhand smoke may have as much as a 30 per cent increase in their risk of lung cancer and heart disease.\u00a0<\/span><\/p>\nTobacco contains\u00a0nicotine<\/a>,<\/strong>\u00a0which is a psychoactive drug. Although nicotine in tobacco smoke does not directly cause cancer<\/a> or most of the other health risks of smoking, it is a highly addictive drug.\u00a0Nicotine is actually even more addictive than cocaine or heroin. The addictive nature of nicotine explains why it is so difficult for smokers to quit the habit, even when they know the health risks and really\u00a0want<\/em>\u00a0to stop smoking. The good news is that if someone\u00a0does<\/em>\u00a0stop smoking, his or her risks of smoking-related diseases and death soon start to fall.\u00a0By one year after quitting, the risk of\u00a0heart\u00a0disease drops to only half of that of a continuing smoker.<\/p>\n\nSmoking and Cancer<\/h1>\n<\/div>\n
One of the main health risks of smoking is cancer, particular cancer of the lung. Because of the increased risk of lung cancer<\/a> with smoking, the risk of dying from lung cancer before age 85 is more than 20 times higher for a male smoker than for a male non-smoker. As the rate of smoking increases, so does the rate of lung cancer deaths, although the effects of smoking on lung cancer deaths can take up to 20 years to manifest themselves, as shown in Figure 13.6.3. Besides lung cancer, several other forms of cancer are also significantly more likely in smokers than non-smokers, including cancers of the kidney, larynx, mouth, lip, tongue, throat, bladder, esophagus, pancreas, and stomach. Unfortunately, many of these cancers have extremely low cure rates.<\/p>\nFigure 13.6.3 Cigarette smoking by men in the U.S. began to decline in the 1950s, but it wasn\u2019t until the 1970s \u2014 roughly 20 years later \u2014 that this was reflected by a concomitant decline in lung cancer deaths in men.<\/em><\/figcaption><\/figure>\nWhen you consider the\u00a0composition\u00a0of tobacco smoke, it\u2019s not surprising that it increases the risk of cancer. Tobacco smoke contains dozens of chemicals proven to be carcinogens, or causes of cancer. Many of these chemicals bind to\u00a0DNA\u00a0in a smoker\u2019s\u00a0cells, and may either kill the cells or cause\u00a0mutations. If the mutations inhibit programmed cell death, the cells can survive to become cancer cells. Some of the most potent carcinogens in tobacco smoke include benzopyrene, acrolein, and nitrosamines. Other carcinogens in tobacco smoke are radioactive isotopes, including lead-210 and polonium-210.<\/p>\n
\nRespiratory Effects of Smoking<\/h1>\n<\/div>\n
Long-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to chronic obstructive pulmonary disease<\/a> (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs’ ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.<\/p>\n\nCardiovascular Effects of Smoking<\/h1>\n<\/div>\n
Inhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of heart attack<\/a> and stroke<\/a>. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.<\/p>\nSmoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.<\/p>\n
\nAdditional Adverse Health Effects of Smoking<\/h1>\n<\/div>\n
A wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:<\/p>\n
\n- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\n
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\n
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\n
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\n
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\n
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\n
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\n
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\n<\/ul>\n\n
Feature: Human Biology in the News<\/h1>\n<\/div>\nFigure 13.6.4 An E-Cigarette or Vape.<\/em><\/figcaption><\/figure>\nThe item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. E-cigarettes<\/span><\/a><\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span><\/p>\nA study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.<\/p>\n
Some manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers’ attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don’t contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.<\/p>\n\n\n13.6 Summary<\/span><\/h1>\n<\/header>\n\n\n- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The nicotine<\/a> in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\n
- A major health risk of smoking is cancer<\/a> of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as carcinogens<\/a>.<\/li>\n
- Smoking is the primary cause of chronic obstructive pulmonary disease<\/a> (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of alveoli<\/a> so the lungs can no longer fully exhale air.<\/li>\n
- Smoking damages the\u00a0cardiovascular system<\/a>\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, heart attack<\/a>, and stroke<\/a>. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\n
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n\n
\n13.6 Review Questions<\/span><\/h1>\n<\/header>\n\n\n- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\n
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\n
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\n
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\n
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\n
- Explain how smoking causes COPD.<\/li>\n
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\n<\/ol>\n<\/div>\n<\/div>\n\n
\n13.6 Explore More<\/span><\/h1>\n<\/header>\n\n
- \r\n \t
- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The [pb_glossary id=\"4366\"]nicotine[\/pb_glossary] in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\r\n \t
- A major health risk of smoking is [pb_glossary id=\"5605\"]cancer[\/pb_glossary] of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as [pb_glossary id=\"4371\"]carcinogens[\/pb_glossary].<\/li>\r\n \t
- Smoking is the primary cause of [pb_glossary id=\"4354\"]chronic obstructive pulmonary disease[\/pb_glossary] (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of [pb_glossary id=\"4311\"]alveoli[\/pb_glossary] so the lungs can no longer fully exhale air.<\/li>\r\n \t
- Smoking damages the\u00a0[pb_glossary id=\"5927\"]cardiovascular system[\/pb_glossary]\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, [pb_glossary id=\"4368\"]heart attack[\/pb_glossary], and [pb_glossary id=\"3103\"]stroke[\/pb_glossary]. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\r\n \t
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n
\r\n 13.6 Review Questions<\/span><\/h1>\r\n<\/header>\r\n
\r\n- \r\n \t
- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\r\n \t
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\r\n \t
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\r\n \t
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\r\n \t
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\r\n \t
- Explain how smoking causes COPD.<\/li>\r\n \t
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\r\n<\/ol>\r\n<\/div>\r\n<\/div>\r\n
\r\n 13.6 Explore More<\/span><\/h1>\r\n<\/header>\r\n
\r\n\r\nhttps:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=emb_logo\r\nBlowing Smoke: The Lost Legacy of the Surgeon General's Report | Alan Blum | TEDxTuscaloosa, TEDx Talks, 2015.<\/p>\r\nhttps:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU\r\n
The dangers of vaping, RWJ Barnabas Health, 2019.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n \r\n
Attributions<\/h2>\r\nFigure 13.6.1<\/strong>\r\n\r\n
\r\n \r\n\r\nCigarette<\/a>\u00a0by \u00a0Uitbundig<\/a>\u00a0on\u00a0Unsplash<\/a>\u00a0is used under the\u00a0Unsplash License<\/a>\u00a0(https:\/\/unsplash.com\/license<\/a>)\r\n\r\nFigure 13.6.2<\/strong>\r\n\r\nRisks_from_smoking-smoking_can_damage_every_part_of_the_body<\/a> by CDC<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.3<\/strong>\r\n\r\nCancer_smoking_lung_cancer_correlation_from_NIH.svg<\/a> by Sakurambo<\/a> on Wikimedia Commons is in the public domain<\/a> (https:\/\/en.wikipedia.org\/wiki\/Public_domain).\r\n\r\nFigure 13.6.4<\/strong>\r\n\r\nAn_Electronic_Cigarette_(11359245033)<\/a> by Lindsay Fox<\/a> from Newport beach, United States on Wikimedia Commons is used under a\u00a0CC BY 2.0<\/a> (https:\/\/creativecommons.org\/licenses\/by\/2.0) license.\r\n\r\n<\/div>\r\n<\/section>\r\nReferences<\/h2>\r\n
Allen, J. G., Flanigan, S. S., LeBlanc, M., Vallarino, J., MacNaughton, P., Stewart, J. H., Christiani, D.C. (2016, June 1). Flavoring chemicals in E-Cigarettes: Diacetyl, 2,3-Pentanedione, and Acetoin in a sample of 51 products, including fruit-, candy-, and cocktail-flavored E-cigarettes [online article]. Environmental Health Perspectives, 124:733\u2013739. <\/em>https:\/\/doi.org\/10.1289\/ehp.1510185<\/span><\/p>\r\n
Health Canada. (2015). Dangers of second-hand smoke [online article]. Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/smoking-tobacco\/avoid-second-hand-smoke\/second-hand-smoke\/dangers-second-hand-smoke.html<\/p>\r\n
RWJ Barnabas Health. (2019, September 25). The dangers of vaping. YouTube. https:\/\/www.youtube.com\/watch?v=QL2-EsjfiAU&feature=youtu.be<\/p>\r\n
TEDx Talks. (2015, August 7). Blowing smoke: The lost legacy of the surgeon general's report | Alan Blum | TEDxTuscaloosa. https:\/\/www.youtube.com\/watch?v=lgVvnnnawvw&feature=youtu.be<\/p>\r\n
Tobacco and Vaping Products Act. (2016, June 26). Government of Canada. https:\/\/www.canada.ca\/en\/health-canada\/services\/health-concerns\/tobacco\/legislation\/federal-laws\/tobacco-act.html<\/p>\r\n
Vaping, E-cigarettes to be regulated by Health Canada. (2016, November 22). CBC\/Radio-Canada. HTTP:\/\/www.cbc.ca\/news\/health\/vaping-health-canada-legislation-1.3862589<\/cite><\/span><\/p>\r\n
Wikipedia contributors. (2020, August 9). Regulation of electronic cigarettes. In\u00a0Wikipedia. <\/i>\u00a0https:\/\/en.wikipedia.org\/w\/index.php?title=Regulation_of_electronic_cigarettes&oldid=972059825<\/p>\r\n
<\/p>","rendered":"
<\/p>\n
Figure 13.6.1 Smoking kills.<\/em><\/figcaption><\/figure>\n \nSure Death<\/h1>\n<\/div>\n
This anti-smoking photo (Figure 13.6.1) clearly makes the point that smoking causes death. The image is not using hyperbole, because smoking actually is<\/em> deadly. It causes about\u00a07\u00a0million deaths each year, and is the single greatest cause of preventable death worldwide. As many as half of all people who smoke tobacco die from it. As a result of smoking\u2019s deadly effects, the life expectancy of long-term smokers is significantly less than that of non-smokers. In fact, long-term smokers can expect their lifespan to be reduced by as much as 18 years, and they are three times\u00a0more\u00a0likely than non-smokers to die before the age of 70.<\/p>\n
\nWhy Is Smoking Deadly?<\/h1>\n<\/div>\n
As shown in Figure 13.6.2, tobacco smoking has adverse effects on just about every bodily system and organ. The detrimental health effects of smoking depend on the number of years that a person smokes and how much the person smokes. Contrary to popular belief, all forms of tobacco smoke \u2014 including smoke from cigars and tobacco pipes \u2014 have similar health risks as those of cigarette smoke. Smokeless tobacco may be less of a danger to the lungs and heart, but it, too, has serious health effects. It significantly increases the risk of cancers of the mouth and throat, among other health problems.<\/p>\n
Figure 13.6.2 Smoking is known to cause many different cancers and chronic diseases.<\/em><\/figcaption><\/figure>\n Even non-smokers may not be spared the deadly risks of tobacco smoke. If you spend time around smokers either at home or on the job, then you are at risk of the dangers of secondhand smoke.\u00a0Secondhand smoke<\/a><\/strong> enters the air directly from burning cigarettes (and cigars and pipes), and indirectly from smokers’ lungs. This smoke may linger in indoor air for hours, and it increases the risk of a wide range of adverse health effects.\u00a0According to Health Canada, second-hand smoke causes 800 deaths from lung cancer and heart disease in non-smokers every year. <\/span>The 2014 U.S. Surgeon General\u2019s Report concluded that there is no established risk-free level of exposure to secondhand smoke. Non-smokers who are exposed to secondhand smoke may have as much as a 30 per cent increase in their risk of lung cancer and heart disease.\u00a0<\/span><\/p>\n
Tobacco contains\u00a0nicotine<\/a>,<\/strong>\u00a0which is a psychoactive drug. Although nicotine in tobacco smoke does not directly cause cancer<\/a> or most of the other health risks of smoking, it is a highly addictive drug.\u00a0Nicotine is actually even more addictive than cocaine or heroin. The addictive nature of nicotine explains why it is so difficult for smokers to quit the habit, even when they know the health risks and really\u00a0want<\/em>\u00a0to stop smoking. The good news is that if someone\u00a0does<\/em>\u00a0stop smoking, his or her risks of smoking-related diseases and death soon start to fall.\u00a0By one year after quitting, the risk of\u00a0heart\u00a0disease drops to only half of that of a continuing smoker.<\/p>\n
\nSmoking and Cancer<\/h1>\n<\/div>\n
One of the main health risks of smoking is cancer, particular cancer of the lung. Because of the increased risk of lung cancer<\/a> with smoking, the risk of dying from lung cancer before age 85 is more than 20 times higher for a male smoker than for a male non-smoker. As the rate of smoking increases, so does the rate of lung cancer deaths, although the effects of smoking on lung cancer deaths can take up to 20 years to manifest themselves, as shown in Figure 13.6.3. Besides lung cancer, several other forms of cancer are also significantly more likely in smokers than non-smokers, including cancers of the kidney, larynx, mouth, lip, tongue, throat, bladder, esophagus, pancreas, and stomach. Unfortunately, many of these cancers have extremely low cure rates.<\/p>\n
Figure 13.6.3 Cigarette smoking by men in the U.S. began to decline in the 1950s, but it wasn\u2019t until the 1970s \u2014 roughly 20 years later \u2014 that this was reflected by a concomitant decline in lung cancer deaths in men.<\/em><\/figcaption><\/figure>\n When you consider the\u00a0composition\u00a0of tobacco smoke, it\u2019s not surprising that it increases the risk of cancer. Tobacco smoke contains dozens of chemicals proven to be carcinogens, or causes of cancer. Many of these chemicals bind to\u00a0DNA\u00a0in a smoker\u2019s\u00a0cells, and may either kill the cells or cause\u00a0mutations. If the mutations inhibit programmed cell death, the cells can survive to become cancer cells. Some of the most potent carcinogens in tobacco smoke include benzopyrene, acrolein, and nitrosamines. Other carcinogens in tobacco smoke are radioactive isotopes, including lead-210 and polonium-210.<\/p>\n
\nRespiratory Effects of Smoking<\/h1>\n<\/div>\n
Long-term exposure to the compounds found in cigarette smoke \u2014 such as carbon monoxide and cyanide \u2014 are thought to be responsible for much of the lung damage caused by smoking. These chemicals reduce the elasticity of alveoli, leading to chronic obstructive pulmonary disease<\/a> (COPD). COPD is a permanent, incurable, and often fatal reduction in the capacity of the lungs, reducing the lungs’ ability to fully exhale air. The chronic inflammation that is also present in COPD is exacerbated by the tobacco smoke carcinogen acrolein and its derivatives. COPD is almost completely preventable simply by not smoking and by also avoiding secondhand smoke.<\/p>\n
\nCardiovascular Effects of Smoking<\/h1>\n<\/div>\n
Inhalation of tobacco smoke causes several immediate responses in the heart and blood vessels. Within one minute of inhalation of smoke, the heart rate begins to rise, increasing by as much as 30 per cent during the first ten minutes of smoking. Carbon monoxide in tobacco smoke binds with hemoglobin in red blood cells, thereby reducing the blood\u2019s ability to carry oxygen. Hemoglobin bound to carbon monoxide forms such a stable complex that it may result in a permanent loss of red blood cell function. Several other chemicals in tobacco smoke lead to narrowing and weakening of blood vessels, as well as an increase in substances that contribute to blood clotting. These changes increase blood pressure and the chances of a blood clot forming and blocking a vessel, thereby elevating the risk of heart attack<\/a> and stroke<\/a>. A recent study found that smokers are five times more likely than non-smokers to have a heart attack before the age of 40.<\/p>\n
Smoking has also been shown to have a negative impact on levels of\u00a0blood\u00a0lipids. Total cholesterol levels tend to be higher in smokers than non-smokers. Ratios of \u201cgood\u201d cholesterol to \u201cbad\u201d cholesterol tend to be lower in smokers than non-smokers.<\/p>\n
\nAdditional Adverse Health Effects of Smoking<\/h1>\n<\/div>\n
A wide diversity of additional adverse health effects are attributable to smoking. Here are just a few of them:<\/p>\n
- \n
- Smokers are at significantly increased risk of developing chronic kidney disease (in addition to kidney cancer). For example, smoking hastens the progression of kidney damage in people with\u00a0diabetes.<\/li>\n
- People who smoke \u2014 especially the elderly \u2014 have a greater risk of influenza and other\u00a0infectious diseases\u00a0than non-smokers. Smoking more than 20 cigarettes a day has been found to increase the risk of infectious diseases by as much as four times the risk in non-smokers. These effects occur because of damage to both the\u00a0respiratory system\u00a0and the immune system.<\/li>\n
- In addition to oral cancer, smoking causes other oral problems, including periodontitis (gum disease). Roughly half of the cases of gum inflammation are attributable to\u00a0current\u00a0or former smoking. This\u00a0inflammation increases the risk of tooth loss, which is also higher in smokers than non-smokers. In addition, smoking stains the teeth and causes halitosis (bad breath).<\/li>\n
- Smoking is a key cause of erectile dysfunction (ED), probably because it leads to narrowing of arteries in the penis, as it does elsewhere in the body. The incidence of ED is about 85 per cent higher in males who smoke than it is in non-smokers.<\/li>\n
- Smoking also has adverse effects on the female reproductive system, potentially causing infertility, in part because it interferes with the body\u2019s ability to produce estrogen. Female smokers are about 60 per cent more likely to be infertile than non-smokers. Pregnant women who smoke or are exposed to secondhand smoke have a higher risk of miscarriages and low-birth-weight infants.<\/li>\n
- Certain therapeutic drugs, including some antidepressants and anticonvulsants, are less effective in smokers than in non-smokers. This occurs because smoking increases levels of liver\u00a0enzymes\u00a0that break down the drugs.<\/li>\n
- Smoking causes an estimated ten per cent of all fire-related deaths worldwide. Smokers are also at a greater risk of dying in motor vehicle crashes and other accidents.<\/li>\n
- Smoking leads to an increased risk of bone fractures, especially of the hip. It also leads to slower wound healing after surgery, and an increased rate of postoperative complications.<\/li>\n<\/ul>\n\n
Feature: Human Biology in the News<\/h1>\n<\/div>\n
Figure 13.6.4 An E-Cigarette or Vape.<\/em><\/figcaption><\/figure>\n The item in Figure 13.6.4 looks like a regular cigarette, but it\u2019s actually an electronic cigarette, or e-cigarette. E-cigarettes<\/span><\/a><\/span>\u00a0are battery-powered devices that change flavored liquids and nicotine into vapor that\u00a0the user inhales. E-cigarettes are often promoted as being safer than traditional tobacco products, and their use is touted as a good way to quit smoking. They are often not banned in smoke-free areas, where it is illegal to smoke tobacco cigarettes.<\/span><\/p>\n
A study completed in 2015 by researchers at the Harvard School of Public Health and widely reported in the mass media found that e-cigarettes may, in fact, be very harmful to the user\u2019s health. E-cigarettes contain nicotine and cancer-causing chemicals, such as formaldehyde. According to the study, about three-quarters of flavored e-cigarettes also contain a chemical\u00a0called\u00a0diacetyl that causes an incurable and potentially fatal disorder of the lungs, commonly called \u201cpopcorn lung\u201d (bronchiolitis obliterans). In this disorder, the bronchioles compress and narrow due to the formation of scar tissue, greatly diminishing the\u00a0breathing\u00a0capacity of people with the disorder. Popcorn lung gained its common name in 2004, when it was diagnosed in workers at popcorn factories. The buttery flavoring used in the factories contained diacetyl.<\/p>\n
Some manufacturers of e-cigarettes and flavorings advertise that their products are now free of diacetyl. However, because e-cigarettes are not currently regulated by the FDA, there is no way of knowing for sure whether the products are actually safe. Equally disturbing is the appeal of flavored e-cigarettes to teens and producers’ attempts to specifically market their products to this age group. Flavors such as \u201ccotton candy,\u201d \u201cKaty Perry\u2019s cherry,\u201d and \u201calien blood\u201d are obviously marketed to youth. Not surprisingly, the use of e-cigarettes is on the rise in middle and high school students, who are more likely to use them than regular cigarettes. Public health officials fear that e-cigarettes will be a gateway for teens to move on to smoking tobacco cigarettes. Some U.S. states have recently passed laws prohibiting minors from buying e-cigarettes, and Brazil, Singapore, Uruguay, and India have banned e-cigarettes. E-cigarettes were not initially regulated by Health Canada because they don’t contain nicotine, which made them illegal to sell, but this was not widely enforced. However, Canada enacted the Tobacco and Vaping Products Act<\/em> (TVPA)<\/a> on May 23, 2018. As more questions are raised about their potential negative health effects, it is likely that more laws will be passed to regulate e-cigarettes. Watch the news for updates on this issue.<\/p>\n
\n\n 13.6 Summary<\/span><\/h1>\n<\/header>\n
\n- \n
- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The nicotine<\/a> in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\n
- A major health risk of smoking is cancer<\/a> of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as carcinogens<\/a>.<\/li>\n
- Smoking is the primary cause of chronic obstructive pulmonary disease<\/a> (COPD). Chemicals such as carbon monoxide and cyanide in tobacco smoke reduce the elasticity of alveoli<\/a> so the lungs can no longer fully exhale air.<\/li>\n
- Smoking damages the\u00a0cardiovascular system<\/a>\u00a0and increases the risk of high\u00a0blood pressure,\u00a0blood\u00a0clots, heart attack<\/a>, and stroke<\/a>. Smoking also has a negative impact on levels of blood\u00a0lipids.<\/li>\n
- A wide diversity of additional adverse health effects are attributable to smoking, such as erectile dysfunction, female\u00a0infertility, and slow wound healing.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n
\n\n 13.6 Review Questions<\/span><\/h1>\n<\/header>\n
\n- \n
- Create a pamphlet aimed at informing teenagers about the dangers of smoking.\u00a0 Include information about numbers of deaths associated with smoking, life expectancy of smokers, and long term healthy effects of smoking and exposure to second-hand smoke.\u00a0 Include a section on the chemicals present in tobacco smoke and e-cigarettes and some of the adverse affects associated with these chemicals.<\/li>\n
- What smoking-related factors determine how smoking affects a smoker\u2019s health?<\/li>\n
- What are the two sources of secondhand cigarette smoke? How does exposure to secondhand smoke affect non-smokers?<\/li>\n
- Why is it so difficult for smokers to quit the habit? How is their health likely to be affected by quitting?<\/li>\n
- Why does smoking cause cancer? List five types of cancer that are significantly more likely in smokers than non-smokers.<\/li>\n
- Explain how smoking causes COPD.<\/li>\n
- Do you think e-cigarettes can be addictive? Explain your reasoning.<\/li>\n<\/ol>\n<\/div>\n<\/div>\n\n
\n 13.6 Explore More<\/span><\/h1>\n<\/header>\n
\n
- A major health risk of smoking is cancer<\/a> of the lungs. Smoking also increases the risk of many other types of cancer. Tobacco smoke contains dozens of chemicals known as carcinogens<\/a>.<\/li>\n
- Smoking is the single greatest cause of preventable death worldwide. It has adverse effects on just about every body system and organ. Tobacco smoke affects not only smokers, but also non-smokers who are exposed to secondhand smoke. The nicotine<\/a> in tobacco is highly addictive, making it very difficult to quit smoking.<\/li>\n
![Risks_from_smoking-smoking_can_damage_every_part_of_the_body<\/a> by](\"https:\/\/commons.wikimedia.org\/wiki\/File:Risks_form_smoking-smoking_can_damage_every_part_of_the_body.png\"){kind=link}
![Cancer_smoking_lung_cancer_correlation_from_NIH.svg<\/a> by](\"https:\/\/commons.wikimedia.org\/wiki\/File:Cancer_smoking_lung_cancer_correlation_from_NIH.svg\"){kind=link}
![An_Electronic_Cigarette_(11359245033)<\/a> by](\"https:\/\/commons.wikimedia.org\/wiki\/File:An_Electronic_Cigarette_(11359245033).jpg\"){kind=link}