THE INFLUENCE OF SMOKING CESSATION ON THE PREVALENCE OF OVERWEIGHT INTHE UNITED-STATES

Background. The proportion of U.S. adults, 35 to 74 years of age who w ere overweight increased by 9.6 percent for men and 8.0 percent for wo men between 1978 and 1990. Since the prevalence of smoking declined ov er the same period, smoking cessation has been suggested as a factor c ontributing to the increasing prevalence of overweight. Methods. To es timate the influence of smoking cessation on the increase in the preva lence of overweight, we analyzed data on current and past weight and s moking status for a national sample of 5247 adults 35 years of age or older who participated in the third National Health and Nutrition Exam ination Survey, conducted from 1988 through 1998. The results were adj usted for age, sociodemographic characteristics, level of physical act ivity, alcohol consumption, and (for women) parity. Results. The weigh t gain over a 10-year period that was associated with the cessation of smoking (i.e., the gain among smokers who quit that was in excess of the gain among continuing smokers) was 4.4 kg for men and 5.0 kg for w omen. Smokers who had quit within the past 10 years were significantly more likely than respondents who had never smoked to become overweigh t (odds ratios, 2.4 for men and 2.0 for women). For men, about a quart er (2.3 of 9.6 percentage points) and for women, about a sixth (1.3 of 8.0 percentage points) of the increase in the prevalence of overweigh t could be attributed to smoking cessation within the past 10 years. C onclusions. Although its health benefits are undeniable, smoking cessa tion may nevertheless be associated with a small increase in the preva lence of overweight.