Tobacco and Its Effects

Introduction Once considered a glamorous and sophisticated habit, smoking is now viewed with increasing disapproval. The recognition of the health risks of smoking is a primary cause of this change in public opinion, and it has led to significant changes in the behavior of many Americans. Over the past four decades, the proportion of cigarette smoking among adults in the United States has dropped 30%. Private businesses and all levels of government have jumped on the nonsmoking bandwagon. Almost every state now restricts smoking bands for indoor workplaces. The U.S. Surgeon General has proposed that America become a completely smoke-free society.

Despite such progress, tobacco use remains widespread. About one in four American adults mokes, and each more than 400,000 Americans die from effects of cigarette smoking. Nonsmokers subjected to the smoke of others also suffer: Exposure to environmental tobacco smoke causes more than 50,000 annual deaths among nonsmokers. Smoking by pregnant women is responsible for about 10% of all infant deaths in this country. Smokeless tobacco and cigars are regaining popularity. The use of smokeless tobacco tripled since 1972; cigar smoking has increased 66% in the last 5 years.

Given the overwhelming evidence against tobacco, why would anyone today begin using it? How does it exercise its hold over users? What can smokers and nonsmokers do to help achieve a tobacco-free society? In this report, we explore answers to these and other questions.

WHY PEOPLE USE TOBACCO If the United States is to become a tobacco-free society, tobacco use must be prevented. This subsection examines the personal and societal forces that induce people to start smoking, as well as the force that encourage them to continue.

Nicotine Addiction The primary reason people continue to use tobacco despite the health risks is that they have become addicted to a powerful psychoactive drug: nicotine. Although the tobacco industry long maintained that there was insufficient evidence about the addictiveness of nicotine, scientific evidence overwhelmingly supports the conclusion that nicotine is highly addictive. In fact, many researchers consider nicotine to be the most physically addictive of all the psychoactive drugs. Recent neurological studies indicate that nicotine acts on the brain in much the same way as cocaine and heroin. Nicotine reaches the brain via the bloodstream seconds after it is inhaled or, in the case of smokeless tobacco, absorbed through the membranes of the mouth and nose. It triggers the release of powerful chemical messengers in the brain, including epinephrine, norepinephrine, and dopamine. But unlike street drugs, most of which are used to achieve a high, nicotine's primary attraction seems to be the ability to modulate everyday emotions.

At low doses, nicotine acts as a stimulant: it increases heart rate and blood pressure and can enhance alertness, concentration, rapid information processing, memory, and learning. People type faster on nicotine, for instance. At high doses, on the other hand, nicotine appears to act as a sedative; it can reduce aggressiveness and alleviate the stress response. Tobacco users may be able to fine-tune nicotine's effects and regulate their moods by increasing or decreasing their intake of the drug. Studies have shown that smokers experience milder mood variation than nonsmokers while performing long, boring tasks or while watching emotional movies, for example.

All tobacco products contain nicotine, and the use of any of them can lead to addiction. Nicotine addiction fulfills the criteria for substance dependence described in Chapter 9, including loss of control, tolerance, and withdrawal.

Loss of Control Three out of four smokers want to quit but find they cannot. Of the 60-80% of people who kick cigarettes at stop-smoking clinics, 75% start smoking again within a year- a relapse rate similar to rates for alcoholics and heroin addicts. Some evidence suggest quitting is even harder for smokeless users: in one study, only 1 of 14 smokeless tobacco users who participated in a tobacco-cessation clinic was able to stop for more than 4 hours.

Regular tobacco users live according to a rigid cycle of need and gratification. On average the can go no more than 40 minutes between doses of nicotine; otherwise, they begin feeling edgy and irritable and have trouble concentrating. If ignored, nicotine cravings build until getting a cigarette or some smokeless tobacco becomes a paramount concern, crowding out all other thoughts. Tobacco users become adept, therefore, at keeping a steady amount of nicotine circulating in the blood and going to the brain. In one experiment, smokers were given cigarettes that looked and tasted alike but varied in nicotine content. The subjects automatically adjusted their rate and depth of inhalation so that they absorbed their usual amount of nicotine. In other studies, heavy smokers were given nicotine without knowing it, and they cut down on their smoking without a conscious effort. Smokeless tobacco users maintain blood nicotine levels as high as those of cigarette smokers.

Tolerance and Withdrawal Using tobacco builds up tolerance. Where one cigarette may make a beginning smoker nauseated and dizzy, a long-term smoker may have to chain-smoke a pack to get the same effects. For most regular tobacco users, sudden abstinence from nicotine produces predictable withdrawal symptoms as well. These symptoms, which come on several hours after the last dose of nicotine, can induce severe cravings, insomnia, confusion, tremors, difficulty concentrating, fatigue, muscle pains, headache, nausea, irritability, anger, and depression. Users undergo measurable changes in brain waves, heart rate, and blood pressure, and they perform poorly on tasks requiring sustained attention. While most of these symptoms pass in 2-3 days, many ex-smokers report intermittent, intense urges to smoke for years after quitting.

Addiction occurs at an early age, despite many teenagers' beliefs that they will be able to stop when they wish to. A 1996 ABC News poll found that about one in three teenagers who tried smoking continued to smoke as a habit. Some 74% stated that they wished they had never started. Another survey revealed that only 5% of high school smokers predicted they would definitely be smoking in 5 years; in fact, close to 75% were smoking 7-9 years later.

CHOOSING HOW TO QUIT There are several methods you can use to quit smoking. How successful any one method will be depends on your personality, how heavily addicted to cigarettes you are, and whether your family, social, school, and work environments will help or hinder your efforts to quit.

Quitting on your own About 85-95% of smokers who quit do it on their own. Studies of successful ex-smokers have shown that support from others and regular exercise is two factors that improve the chances of success. On the flip side, the more alcohol one drinks, the less successful one will be at quitting smoking. Some people quit "cold turkey," while others taper down more slowly.

Help from the Pharmacy Nicotine replacement therapy involves supplying the tobacco user with nicotine from a source other than standard tobacco products. It allows a tobacco user to overcome the psychological and behavioral aspects of a tobacco habit without having to simultaneously endure the physical symptoms of nicotine withdrawal. Nicotine replacements are found in chewing gum and skin patches; both products are available without a prescription. Each piece of gum delivers about as much nicotine as one cigarette; each patch delivers a timed dose of nicotine equal to as much as three-quarters over a 24-hour period. After a few weeks or months, the reforming tobacco user begins to taper off use of the replacement, avoiding withdrawal symptoms. Some brands of nicotine patches come in several strengths to make it easier to decrease the dosage.

There are drawbacks to nicotine replacement therapy. Many people find it difficult to manage the dosage of nicotine while using the gum. Possible side effects include burning sensations in the mouth and throat, nausea, and vomiting. The patch can cause skin irritation, nausea, dry mouth, and nervousness. People who continue to smoke while using a nicotine replacement risk nicotine overdose and possibly heart attack. Moreover, some people become hooked on the gum or patch.

Nicotine replacements can be effective in helping some people quit, especially when used in combination with counseling and behavioral therapy.

Help from Your Physician The FDA approved nicotine replacement therapy in the form of an inhaler for prescription use in 1997. A physician may also prescribe additional medications for very heavy smokers or those who have tried unsuccessfully to quit. Some people are helped by clonidine, a drug used to aid heroin addicts during withdrawal. Others benefit from antidepressants or anti-anxiety drugs. Your physician may have other resources to share with you that are unique to your community, such as cessation programs, support programs, or a hotline number.