Smoking and Smokeless Tobacco

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Respiratory cilia	Secondhand Smoke and Lung Cancer	Tobacco and cancer	Tobacco and chemicals
Tobacco and vascular disease	Tobacco health risks

Second-hand smoke; Cigarette smoking; Cigar smoking; Pipe smoking; Smokeless snuff; Tobacco use

Tobacco is a plant grown for its leaves, which are smoked, chewed, or sniffed for a variety of effects. It is considered an addictive substance because it contains the chemical nicotine.

In addition to nicotine, tobacco contains over 19 known cancer-causing chemicals (most are collectively known as "tar") and more than 4,000 other chemicals. These include acetone, ammonia, carbon monoxide, cyanide, methane, propane, and butane.

Over 38 million people in the United States have successfully quit smoking. Yet there are still around 50 million Americans who smoke. The majority say they would like to quit.

And, while the number of cigarette smokers in the United States has dropped over recent years, the number of smokeless tobacco users has steadily risen. This trend is likely related to the false belief that smokeless tobacco is safe. It is NOT. Smokeless tobacco carries many of the same health risks as cigarettes. Some people who want to stop smoking, but who still crave the nicotine, turn to smokeless tobacco wrongly thinking that they are doing something good for themselves.

THE EFFECTS OF NICOTINE

• Nicotine acts as both a stimulant and depressant on your body. It increases your bowel activity, saliva, and bronchial secretions. It stimulates the nervous system and may cause tremors in the inexperienced user, or even convulsions with high doses.
• After stimulation, there's a phase that depresses the muscles in your airways. As a euphoric agent, nicotine causes relaxation from stressful situations.
• On average, tobacco increases your heart rate 10 to 20 beats per minute, and it increases your blood pressure reading by 5 to 10 mmHg (because it constricts the blood vessels).
• Nicotine may also cause sweating, nausea, and diarrhea. Nicotine elevates the blood level of glucose (blood sugar) and increases insulin production. Nicotine also tends to enhance platelet aggregation, which may lead to blood clots.
• Nicotine temporarily stimulates memory and alertness. People who use tobacco frequently depend on it to help them accomplish certain tasks at specific levels of performance. Nicotine also tends to be an appetite suppressant. (For this reason, fear of weight gain also influences the willingness of some people to stop smoking.)