For smokers who don’t quit, cutting back seems to help

The question: The advice from health experts is clear: If you smoke, quit. But not everyone stops. For those who continue, might reducing the number of cigarettes smoked reduce the chances of developing lung cancer?

This study analyzed health data on 19,714 adults, including people who smoked, those who didn’t and those who had quit. Over an average of 18 years, 864 participants were diagnosed with lung cancer. Heavy smokers (more than 15 cigarettes daily) who reduced number of daily cigarettes by half or more during this time were 27 percent less likely to develop lung cancer than were those who did not cut back. Compared with those who continued heavy smoking, ex-smokers – people who had stopped before the study started – were 83 percent less likely to develop lung cancer, and those who quit during the study showed a 50 percent reduction in risk.

Who may be affected by these findings? Adults who smoke. Although cigarette smoking has declined in the last 40 years, about 46 million U.S. adults still smoke – roughly one-fourth of all men and one-fifth of all women. About 90 percent of lung cancer cases stem from smoking.

Caveats: Data on smoking habits were based on reports from the participants. The authors stated that smoking cessation, not just reduction, remains the best way to limit harm from smoking.

Find this study Sept. 28 issue of the Journal of the American Medical Association; abstract available online at www.jama.com.

Learn more about the health consequences of smoking at www.cancer.org (search for “tobacco”) and www.cdc.gov/tobacco.