Cigarette smoking has been the most popular method of taking nicotine since the beginning of the 20th century.

Statistics:

• About 62 million Americans (29%) are current cigarette smokers, and approximately 153 million people have tried smoking at least once, making nicotine one of the most heavily used addictive drugs in the U.S.
• Worldwide, tobacco kills over 2% million people prematurely every year. Smoking kills more Americans each year than alcohol, cocaine, crack, heroin, homicide, suicide, auto accidents, fires and AIDS combined.
• Tobacco smoke is classified by the EPA as a class "A" carcinogen, along with asbestos and benzene.
• 12 million Americans use smokeless tobacco (snuff and chew), and 4 million of those are under 21.
• Smokeless tobacco has over 2,000 chemicals, among them: Polonium-210 (nuclear waste); N-Nitrosamines (cancer-causing chemical); Formaldehyde (embalming fluid); Nicotine (addictive drug); Cadmium (used in car batteries); Cyanide; Arsenic; Benzene and Lead (nerve poison).

The effects of Nicotine:

Nicotine is both a stimulant and sedative to the central nervous system. It is absorbed in the lungs when it is smoked, and also absorbed when it is chewed.  Women who smoke generally have earlier menopause; pregnant women who smoke are at an increased risk of having stillborn, premature or low birth weight infants.  Kids who take smokeless tobacco are more likely than non-users to begin smoking.  Cigarette smoke is composed of about 12 gases, including carbon monoxide and tar. The tar in cigarettes exposes the smoker to increased risk of lung cancer, emphysema and bronchial disorders. The carbon monoxide increases the chances of cardiovascular disease.  Nicotine produces effects on the head, lungs, stomach, and the nervous system. Short-term effects include sweating, vomiting and throat irritation. Long-term effects include increased head rate and blood pressure. The most serious effects are lung cancer and stroke. Cancers of the esophagus, mouth, lips and larynx are also associated with cigarette smoking.  Chewing tobacco is not safer than cigarettes just because there's no smoke. It has the same effects on the body as smoking cigarettes, and also has an increased risk of oral cancers, and cancers of the throat, cheek and gums. Spit tobacco permanently discolors teeth. Chewing tobacco causes bad breath. Its direct and repeated contact with the gums causes them to recede, which can cause your teeth to fall out. Spit tobacco contains a lot of sugar which, mixed with the plaque on your teeth, forms acid that eats away at tooth enamel, causes cavities and chronic painful sores.