Body mass decrease after initial gain following smoking cessation

Background Although smoking cessation is strongly associated with subsequen t weight gain, it is not clear whether the initial gain in weight after smo king cessation remains over time. Method Cross-sectional analyses were made, using data from periodic health examinations for workers, on the relationship between body mass index (BMI) and the length of smoking cessation. In addition, linear regression coeffi cients of BMI on the length of cessation were estimated according to alcoho l intake and sport activity, to examine the modifying effect of these facto rs on the weight of former smokers. Results Means of BMI were 23.1 kg/m(2), 23.3 kg/m(2), 23.6 kg/m(2) for ligh t/medium smokers, heavy smokers and never smokers, respectively. Among form er smokers who had smoked greater than or equal to 25 cigarettes a day, odd s ratio (OR) of BMI >25 kg/m(2) were 1.88 (95% confidence interval [CI] : 1 .05-3.35), 1.32 (95% CI:0.74-2.34), 0.66 (95% CI:0.33-1.31) for those with 2-4 years, 5-7 years, and 8-10 years of smoking cessation, respectively. Th e corresponding OR among those who previously consumed <25 cigarettes a day were 1.06 (95% CI:0.58-1.94), 1.00 (95% CI:0.58-1.71), and 1.49 (95% CI:0. 95-2.32). Conclusions The results suggest that although heavy smokers may experience large weight gain and weigh more than never smokers in the few years after smoking cessation, they thereafter lose weight to the never smoker level, w hile light and moderate smokers gain weight up to the never smoker level wi thout any excess after smoking cessation.