The present study examined nicotine replacement effects on postcessation weight gain in smoking cessation clinic volunteers using objective indices of cigarette smoking, gum use, and body weight. After they achieved abstinence, subjects were randomly assigned to either active nicotine or placebo gum conditions for 10 weeks, during which smoking status was carefully monitored. Analyses revealed strong evidence for a gum effect on weight gain, with active gum users gaining a mean total of 3.8 lb compared with 7.8 lb for placebo gum users at the end of the 10-week trial. Evidence for a dose-response relation was found, suggesting that more gum use (greater than or equal to 6.5 pieces/day) resulted in greater weight suppression. Placebo gum subjects reported greater postcessation increases in eating and hunger compared with active gum subjects. The implications of the weight suppression effect of nicotine gum for smoking cessation treatments are discussed.