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Smoking Cessation Health Center

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Effects of Secondhand Smoke


Cancer is probably the most discussed health repercussion of smoking, and it's also a significant problem with secondhand smoke exposure. Lung cancer may be the most talked about effect of secondhand smoke exposure, but the risks of breast cancer, cervical cancer, and other types of cancer are also thought to be higher.

Heart Disease

Breathing in secondhand smoke is bad for your heart, and research shows that it takes as little as 10 minutes for the smoke to start causing damage. Smoke exposure makes your blood platelets stickier, raises the level of artery-clogging LDL "bad" cholesterol, and damages the lining of your blood vessels. Eventually, these changes can make you more likely to develop a blockage that leads to a heart attack or stroke. Researchers have found that women who have been exposed to secondhand smoke face a 69% higher risk of heart disease and a 56% higher risk of stroke than those who haven't been exposed.

Children and Secondhand Smoke

Children are particularly vulnerable to the effects of secondhand smoke because their bodies are still growing and they breathe at a faster rate than adults.

All of these conditions have been attributed to secondhand smoke exposure in children:

  • Sudden infant death syndrome (SIDS)
  • Increased number of respiratory infections (such as bronchitis and pneumonia)
  • More severe and frequent asthma attacks
  • Ear infections
  • Chronic cough

Smoking during pregnancy is especially dangerous to the developing baby. It has been linked to premature delivery, low birth weight, SIDS, mental retardation, learning problems, and attention deficit hyperactivity disorder (ADHD). The more cigarettes a mother-to-be smokes, the greater the danger to her unborn baby.

How to Avoid Secondhand Smoke

The best way to lower your risk of all these conditions is to avoid smoking, and to convince those around you who smoke to quit. Anyone who does smoke should do so outside, as far away from nonsmokers as possible.

The home is probably the most important place to keep smoke-free, especially when children live there. An estimated 21 million children live in homes where a resident or visitor regularly smokes, and more than half of all American kids have detectable levels of cotinine (the breakdown product of nicotine) in their blood. Keeping kids (and adults) far away from smoke can help reduce their risks of developing respiratory infections, severe asthma, cancer, and many other dangerous health conditions.


WebMD Medical Reference

Reviewed by Varnada Karriem-Norwood, MD on May 26, 2014

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