Weight gain after cessation of cigarette smoking. A possible role for adipose-tissue lipoprotein lipase.

Cigarette smokers weigh less than nonsmokers and gain weight when they stop smoking. Increased activity of lipoprotein lipase in adipose tissue in some smokers may represent a compensatory response to their reduced body weight. Consequently, we hypothesized that the enzyme's activity may be related to the rate at which smokers gain weight when they stop smoking. To test this hypothesis, we measured body weight and fasting lipoprotein lipase activity in adipose tissue in 15 cigarette smokers before they stopped smoking. The changes in body weight during the first two weeks of abstinence were correlated with the base-line lipase activity in these smokers (r = 0.82, P less than 0.0002). This relation remained significant in the 12 subjects who were still abstinent at three weeks (r = 0.63, P less than 0.03). These results suggest that lipoprotein lipase activity in adipose tissue has a counterregulatory role in the maintenance of body weight and adipose-tissue mass in smokers. The higher the level of lipase activity when the weight-reducing influences of cigarettes cease, the greater the rate at which weight is gained during the first three weeks of abstinence.