From an article in Science News (Nov. 28):

Smoking cigarettes causes about half of all coronary artery disease cases among young and middle-aged women in the United States, according to a Harvard University study released last week.

The study also showed that women who stopped smoking drastically reduced their chances of developing coronary artery disease and that no level of smoking was safe for women. In addition, several other risk factors, such as diabetes and hypertension, were found to significantly increase a woman smoker's chances of developing coronary artery disease, which includes fatal and nonfatal heart at-tacks and periodic chest pain, orangina.

"Cigarette smoking is the single most avoidable risk factor for heart attacks in young and middle-aged women," says the study's principal author, Walter C. Willett of the Harvard School of Public Health.

For many years, studies showed that smoking among men -- but not among women -- was associated with coronary artery disease. But researchers now say the studies looking only at women were flawed because the samples were too small.

In recent years, the association among women has been established. And according to the researchers, the Harvard study is the largest study to report the association, which shows that men and women smoking the same number of cigarettes have about the same chance of developing coronary artery disease.