Cigarette smoking damages the lungs, blood vessels, and, to a lesser extent, other organs, such as the heart.
Cancer of the lung is a serious health hazard; the peak of its incidence in men occurs in the 55 to 65 age group (when 1 in 7 deaths results from lung cancer). Approximately 2 out of every 5 heavy smokers die before the age of 65. In women who smoke, the highest mortality rate occurs 10 years earlier than in men, and 1 death in 3 caused by lung cancer will be that of a woman.
People who smoke not only damage their own health, but also harm others. For instance, a pregnant woman who smokes harms her unborn child; children exposed to smoke have more respiratory illnesses; a person who suffers from heart disease may be adversely affected by other persons' smoke; and people who live or work in smoky environments have an increased risk of developing respiratory ailments. In the last several years, many governmental agencies and private companies have instituted policies that limit or ban smoking in public areas.
Although the sale of cigarettes to persons below the age of 18 is not allowed in the United States and other countries, tobacco remains one of the most easily obtained addictive drugs.
Q: What are the harmful substances in tobacco and what do they do?
A: There are four main groups of dangerous substances in tobacco smoke. Nicotine is the substance that causes addiction. It stimulates the release of epinephrine and other substances in the body that cause an increase in pulse rate, a rise in blood pressure, and a narrowing of the blood vessels in the skin. Epinephrine also causes an increase in fatty substances in the blood and makes blood platelets (factors in blood clotting) stickier and therefore more likely to form blood clots.
Carbon monoxide is a poisonous gas produced by the incomplete burning of tobacco. In the lungs, it combines with hemoglobin in the blood and thus prevents the hemoglobin from carrying its full quota of oxygen throughout the circulation. It reduces a person's physical fitness and also acts as a poison.
Various substances in tobacco irritate the lining of the bronchi, inducing spasm and increasing bronchial secretions. At the same time, these irritants damage cells that usually sweep the secretions out of the lungs. This increases the likelihood of developing bronchitis.
Cancer-producing substances are present in the tar in cigarette smoke.
Q: Is there any way of reducing the dangers of cigarette smoking?
A: Yes. Obviously, the best way of avoiding the dangers of cigarette smoking is to give up the habit. Cigarettes, preferably with filters, should be smoked to a long stub, not a short one. Removing the cigarette from the mouth between puffs helps reduce the amount of smoke that is inhaled. Nicotine chewing gum is of moderate value as an adjunct to behavioral or psychological therapy for physically dependent smokers who wish to quit entirely. Recently transdermal continuous low-level nicotine systems have become available, allowing a replacement of part of the nicotine level obtained by smoking. These nicotine patches have been more effective than the gum. The patches are contraindicated in nonsmokers, pregnant women, and patients with a recent heart attack, life-threatening heart rhythm disturbances, or unstable angina.
Q: What effect does smoking during pregnancy have on the fetus?
A: Babies born to mothers who smoke are 5 to 13 ounces (140 to 364 g) lighter on average than those born to nonsmoking mothers. Also, pregnant women who smoke are more likely to have a miscarriage, stillborn baby, or infant that dies soon after birth. Twice as many premature babies are born to smoking mothers as to nonsmoking mothers. Evidence also suggests that by the age of 11 the children of mothers who smoked more than 10 cigarettes a day during pregnancy are slightly shorter and slightly below average in reading, math, and general ability than children of non-smoking mothers.
Q: What are the effects of smoking on the lungs?
A: Chronic bronchitis and, eventually, emphysema commonly occur in heavy smokers, and a morning cough is a common feature of all smokers. Early lung damage can be detected by pulmonary function tests before there is any obvious shortness of breath.
Among persons who smoke a pack of cigarettes a day, lung cancer occurs 20 times more frequently than in nonsmokers. The risk is increased in those who smoke high-tar cigarettes, who inhale deeply, and who began smoking in adolescence.
Q: Can smoking cause other cancers?
A: Yes. There are more cancers of the bladder and pancreas in smokers than in nonsmokers. Cancer of the mouth, tongue, larynx, and esophagus are also more common in smokers of all kinds of tobacco.
Q: Can smoking affect the heart?
A: Cigarette smoking increases the likelihood of arteriosclerosis and doubles the risk of coronary thrombosis. The risk of developing other blood vessel disorders is also increased.
Q: What other diseases are more likely to occur in smokers?
A: Dental and gum disorders occur more commonly in smokers. Smokers are also more likely to develop tuberculosis, probably because the damaging effect of the irritants in tobacco lowers the resistance of the lungs to this type of infection.
Although smoking does not cause peptic ulcers, the continued habit prevents them from healing. Consequently, complications are more common and mortality is greater from perforated ulcers.
Q: What are the benefits of stopping smoking?
A: Within a few days or weeks, there is an improvement in the sense of taste and smell, a gradual reduction in the amount of morning coughing, and less shortness of breath during exercise. There is often a temporary increase in phlegm production.
Although lung damage, such as that caused by chronic bronchitis and emphysema, cannot be reversed once it has occurred, its progress is arrested.
However, the greatest long-term benefit is the steady decrease in the chances of getting cancer. If a person who stops smoking cigarettes lives for 10 years, his or her chance of developing lung cancer is no more than for someone who has never smoked.
