THE IMPACT OF CIGARETTE AND ALCOHOL-CONSUMPTION ON WEIGHT AND OBESITY- AN ANALYSIS OF 1911 MONOZYGOTIC MALE TWIN PAIRS

Background: The objective of this investigation was to examine the rel ationships among cigarette and alcohol consumption and weight and obes ity. Although previous research demonstrated that smoking is associate d with reduced weight, data on the relationship between alcohol consum ption and weight are conflicting. In addition, the influence of smokin g cessation on the risk of obesity at a level that adversely affects h ealth has not been fully examined. Methods: By means of a cotwin-contr ol research design, cigarette and alcohol consumption and weight measu rements derived from 1911 male, monozygotic twins were compared with t hose of their identical siblings. This approach eliminates confounding from a large number of measurable and unmeasurable environmental expe riences and the well-documented influence of inherited factors on weig ht and cigarette and alcohol consumption. Results: After adjustment fo r a variety of socioeconomic factors, light (one to 19 cigarettes dail y), moderate (20 to 29 cigarettes daily), and heavy (>29 cigarettes da ily) smokers were an average of 3.2, 2.4, and 4.0 kg lighter, respecti vely, than nonsmokers. Past smokers demonstrated a 33% higher prevalen ce of clinically significant obesity (body mass index >27.8 kg/m2) by comparison with their currently smoking siblings (26.5% vs 19.9%, resp ectively; difference, P<.001) and a 1.8 times increased risk (95% conf idence interval, 1.1 to 2.9) of clinically significant obesity by comp arison with heavy smokers. By contrast, alcohol consumption had no sig nificant influence on weight or obesity. Conclusions: Smoking cessatio n efforts provided by health practitioners to men should consider rout inely offering a weight management component to reduce weight gain and further improve the well-documented health benefits of not smoking. I t may not be necessary for alcohol treatment programs to adopt a simil ar policy.