NICOTINE

Found in: cigarettes, cigars, chewing tobacco, nicotine gum, and patches.

Source: Tobacco plant.

Legal code: Legal if you are over 18.

History: Tobacco was used in the 1500s to treat headaches, colds, and other medical problems and was even thought to be holy because of its healing reputation. This view gradually gained opposition and by 1890 nicotine was discontinued as a medicine in the United States, although tobacco remained very popular, particularly chewing tobacco. Cigar and cigarette smoking caught on in America in the 1900s and rose to a peak in the mid-1960s, when 40 percent of all adults were smokers. This number has declined to 25 percent in the 1990s for a few possible reasons: the ban on cigarette advertising on TV; authoritative studies linking smoking to very serious health problems, especially deadly cancer; and an effective educational campaign using this knowledge.

Effects: Nicotine stimulates the heart and circulation. It can increase concentration and attention. Smokers report that it helps to relieve anxiety and stress.

Risks: Cigarette smoking is the major cause of preventable deaths in America. Tobacco users or those living with smokers have nearly all the cases of lung cancer, a two times greater risk of fatal heart disease, a two to three times greater chance of peptic ulcers, and a several times greater risk of throat, mouth, esophageal, pancreatic, kidney, bladder, and cervical cancer. On average, people who smoke die 5 to 8 years earlier than people who do not smoke. Smokers get more colds, tend to have a year-round cough, and eventually develop emphysema. Sooner or later they also experience a deadened sense of smell and taste, premature and more face wrinkles, yellow teeth (and fingertips from tobacco stains), and increased heart rate and blood pressure. Nonsmokers also experience some of these risks if they are constantly exposed to second-hand smoke. Part of the rationale behind nonsmoking bars and restaurants is consideration of the health of people who work in these environments.

Risks for teens: People who start smoking as teenagers put themselves at much higher risk for nicotine addiction. Recent studies show that early smoking permanently scars the DNA structure of the lungs, leaving them vulnerable to future lung disease even if teen smokers quit later in life. Adolescent smokers are twice as likely to suffer a major episode of depression. Teens with long-term depression are more likely to be smokers. Dangerous nicotine overdose may be very rare, but it's possible. Nicotine poisoning can cause nausea, weakness, and dizziness. Nicotine can cause serious and permanent damage to an unborn fetus. If you think you may be pregnant, do not smoke!

Do not combine with: Cocaine or other drugs that increase heart rate or blood pressure--it can increase risk of heart attack.

Addiction rating: High.

Quitting: Serious cravings for nicotine decrease quickly within days of quitting, and nicotine gum or the patch can help during this time. Much harder to deal with are the habits and psychological associations people have developed around smoking over time (certain friends, places, and routines can trigger the urge). And many people worry about weight gain after quitting. Smoking both accelerates the body's metabolism and gives you something non-caloric to stick in your mouth. Although weight gain is usually only temporary and can be kept to a minimum, the best solution is to substitute exercise for smoking. There are many programs available to help you quit if you find that you can't do it alone.