Smoking cessation and weight gain.

Cigarette smokers have a lower average body weight than nonsmokers, and the cessation of smoking is associated with weight gain. Although this weight gain does not offset the health benefits of smoking cessation, it is frequently a source of concern for smokers planning to quit. The objective of our review was to estimate the risk and duration of weight gain after cessation of smoking to help physicians in counseling concerned smokers. We reviewed the literature by doing a MEDLINE search using key words for articles on the changes in body weight after smoking cessation. The retrieved data indicated that (1) the risk of weight gain is highest during the 2 years immediately following smoking cessation, and declines thereafter; (2) on average, sustained quitters gain about 5 to 6 kg in weight; (3) physical exercise, older age, higher baseline body mass index, and lower rates of smoking attenuate the degree of weight gained after smoking cessation; and (4) the evidence regarding the permanence of the expected weight gain is conflicting.