The Effects of Secondhand Smoke

Being around tobacco smoke is bad for you, even if it's someone else's smoke.

When someone smokes a cigarette, most of the smoke doesn't go into their lungs. It goes into the air, where anyone nearby can breathe it.

Smoking is banned in many public places. But many people are still exposed to secondhand smoke, especially children who live with parents who smoke. Even people who try to be careful about where they light up may not protect those around them.

What Is Secondhand Smoke?

It can come from a cigarette, cigar, or pipe. Tobacco smoke has more than 4,000 chemical compounds, at least 250 are known to cause disease.

Exposure to secondhand smoke raises the risk -- by as much as 30 percent -- that others will get lung cancer and many other types of cancer, it can lead to emphysema, and it is bad for your heart. 

Smoke makes your blood stickier, raises your "bad" LDL cholesterol, and damages the lining of your blood vessels. Eventually, these changes can make you more likely to have a heart attack or stroke.

Dangers for Children

Kids are particularly at risk for the effects of secondhand smoke because their bodies are still growing and they breathe at a faster rate than adults.

These conditions have been linked to secondhand smoke exposure in children:

Smoking during pregnancy is especially dangerous to the developing baby. It's tied to premature delivery, low birth weight, SIDS, limited mental ability, trouble with learning, and ADHD. The more cigarettes a mother-to-be smokes, the greater the danger to her baby.

How to Avoid Secondhand Smoke

It's simple: Avoid being around people who are smoking, and try to convince those around you who smoke to quit. Anyone who does smoke should do so outside, as far away from other people as possible.

Your home is probably the most important place to keep smoke-free, especially if you have children. Keeping kids (and adults) far away from smoke can help lower their chances of having respiratory infections, severe asthma, cancer, and many other serious conditions.

WebMD Medical Reference Reviewed by William Blahd, MD on July 14, 2017

Sources

SOURCES:

American Cancer Society: "Secondhand Smoke."

Office of the Surgeon General: "The Health Consequences of Involuntary Exposure to Tobacco Smoke: A Report of the Surgeon General," June 27, 2006.

National Cancer Institute: "Secondhand Smoke: Questions and Answers."

CDC: "Secondhand Smoke: What it Means to You." 

CDC: "Trends in Secondhand Smoke Exposure."

He Y. Circulation, 2008.

American Heart Association: "Toddlers affected most by secondhand exposure at home."

American Lung Association: "Secondhand Smoke Fact Sheet."

American Heart Association: "Smoking: Do You Really Know the Risks?"

CDC: "Cigarette Smoking in the United States."

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