An irreversible health effect is a permanent change in the structure and/or function of an organ system or a permanently increased risk of suffering from a disease or some other threat to health. Irreversible effects vary in intensity and are related both to the amount and duration of exposure and the age at which the person is initially exposed. A risk or effect may diminish over time, but it may also increase; some risk may remain many years after exposure has ended.

Executive Summary

This report examines the irreversible effects of cigarette smoking on various organ systems and challenges the notion that a few years of exposure to smoking will have no lasting adverse consequences. Our hope is to discourage young people from taking up this deadly habit by appealing to their common sense and better judgment, thereby allowing them to choose for themselves not to smoke. We will not recite the familiar litany of smoking-related health problems such as emphysema, cancer, and heart disease. Rather, we will show that smoking cigarettes for as few as five years can have a permanent effect on the lungs, the heart, the eyes, the throat, the urinary tract, the digestive organs, the bones and joints, and the skin—even if the smoker quits.

We do not mean to dishearten long-term smokers. Despite smoking's irreversible effects, it would be foolish for a smoker to conclude that, after years of smoking, quitting would do him no good. Many studies prove that tobacco-related health effects decline substantially as time away from smoking increases; some of the benefits begin within months after quitting. But after years of exposure to the damaging effects of tobacco, quitting smokers must realize that they have to be realistic in their expectations of recouping their health.

For our latest work on tobacco issues, please see: http://www.acsh.org/healthissues/categoryID.8/category_detail.asp

For our blog (on tobacco and other issues), please visit: http://www.acsh.org/factsfears/

To learn the specific, detailed health effects of smoking, in our site geared toward teens, check out: http://theScooponSmoking.org