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Smoking and smokeless tobacco

Contents of this page:


Tobacco and vascular disease
Tobacco and vascular disease
Tobacco and chemicals
Tobacco and chemicals
Tobacco and cancer
Tobacco and cancer
Secondhand smoke and lung cancer
Secondhand smoke and lung cancer
Respiratory cilia
Respiratory cilia
Tobacco health risks
Tobacco health risks

Alternative Names    Return to top

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

Information    Return to top

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.


Finally, tobacco is highly addictive. It is considered mood and behavior altering. Tobacco is believed to have an addictive potential comparable to alcohol, cocaine, and morphine.


There are many reasons to quit using tobacco. Knowing the serious health risks may help motivate you to quit. When used over a long period, tobacco and related chemicals such as tar and nicotine can increase your risk of:

You have the same risks if you use smokeless tobacco (chewing tobacco, snuff, etc.) for a long time. In addition, smokeless tobacco users have a 50 times greater risk for mouth cancer than those who do not use such products.


Those who are regularly around the smoke of others (secondhand smoke) have a higher risk of:

Infants and children that are exposed regularly to secondhand smoke are at risk of:


There are a lot of ways to quit smoking and many resources to help you. Family members, friends, and coworkers may be supportive or encouraging, but the desire and commitment to quit must be your own.

Most people who have been able to successfully quit smoking made at least one unsuccessful attempt in the past. Try not to view past attempts to quit as failures, but rather as learning experiences.

Feel ready to quit? Here are some tips:

Like any addiction, quitting tobacco is difficult, particularly if you are acting alone. If you join smoking cessation programs, you have a much better chance of success. Such programs are offered by hospitals, health departments, community centers, and work sites.

The best quit-smoking programs combine multiple strategies, including peer support and ways to overcome potential relapse situations. Counseling by telephone can be a very helpful reinforcement, even as effective as face-to-face counseling.

Short-term use of the antidepressant medication bupropion (Wellbutrin, Zyban), along with a quit-smoking program, may increase your success. Bupropion requires a prescription from your health provider and should not be used if you have a history of seizures or kidney failure.

If you aren't successful the first time, simply look at what occurred or what didn't work, develop new strategies, and try again. Many attempts are often necessary to finally "beat the habit."



Call your doctor if you are a smoker and:

Other resources include local chapters of the American Lung Association and the American Cancer Society. Both organizations have a wide range of resource materials and comprehensive smoking cessation programs.

References    Return to top

Metz CN, Gregersen PK, Malhotra AK. Metabolism and biochemical effects of nicotine for primary care providers. Med Clin North Am. 2004;88:1399-1413.

Anderson JE, Jorenby DE, Scott WJ, Fiore WC. Treating tobacco use and dependence: an evidence-based clinical practice guideline for tobacco cessation. Chest. 2002;121:932-941.

Parkes GT, Greenhalgh T, Griffin M, Dent R. Effect on smoking quit rate of telling patients their lung age: the Step 2 quit randomised controlled trial. BMJ. 2008:336:598-600.

Update Date: 6/19/2008

Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

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