The American Psychological Association's annual meeting is the world's largest gathering of psychologists. This year, the 93rd annual meeting drew some 11,000 participants to lectures (including one by psychologist B.F. Skinner), presentations of hundreds of papers and symposiums on a variety of topics. Among them was this report on gender differences in breaking the cigarette habit:

Women who quit smoking "may tend to gain more weight than male ex-smokers," concludes an ongoing study of nicotine effects by psychologist Neil Grunberg and his colleagues at the Uniformed Services University of Health Sciences in Bethesda.

Past studies by Grunberg showed that ex-smokers could avoid some of the extra pounds associated with quitting by eliminating sugar and high-calorie sweet foods from their diet, or by using sugar substitutes.

Nicotine seems to suppress the desire for sweet foods, so when someone quits smoking, their sweet tooth tends to run amok.

Other research from his lab indicated that smokers tend to decrease their physical activity when they quit. A conscious effort to increase exercise, he found, could help prevent weight gain.

Those findings still hold true for males, but the latest evidence suggests that there are some important gender differences in smoking cessation.

Female rats showed increases in both water and food consumption after the researchers stopped administering nicotine, but male rats showed an increase in food consumption only if sweet foods were available.

"It may be particularly important for women to control [all] eating and drinking behavior," not just sweets, he says, "in order to avoid weight gain after cessation of cigarette smoking."

Moreover, while male rats showed decreased activity after nicotine was stopped, he found that female rats did not. Increasing exercise during withdrawal from nicotine does not appear to be as beneficial for women in keeping weight off as it is for men, he says.