Associations of alcohol drinking and cigarette smoking with serum lipid levels in healthy middle-aged men.

AIMS The aim of this study is to determine whether influences of drinking alcohol on serum lipid levels are different in smokers and non-smokers. METHODS Subjects were 25,689 healthy male workers aged 40 to 59 years. Serum total and HDL cholesterol and triglyceride concentrations were measured and LDL cholesterol concentrations were estimated by using the Friedewald formula. The subjects were divided into three groups by average daily consumption of cigarettes (non-smokers; light smokers, less than 20 cigarettes per day; heavy smokers, 20 or more cigarettes per day) and by average daily alcohol consumption (non-drinkers; light drinkers, less than 30 g of ethanol per day; heavy drinkers, 30 g or more of ethanol per day). RESULTS In overall subjects, serum HDL, LDL and total cholesterol were significantly lower and triglyceride was significantly higher in heavy smokers than in non-smokers. In the smoker groups, serum total cholesterol was significantly lower in heavy drinkers than in non-drinkers, while no difference in total cholesterol was observed in non- and heavy drinkers of the non-smoker group. Both in the smoker and non-smoker groups, HDL cholesterol was higher and LDL cholesterol was lower in drinkers than in non-drinkers. The difference in LDL cholesterol between non-drinkers and drinkers was more prominent in smokers than in non-smokers. The above associations were not altered after the adjustment for age, body weight and alcohol intake. CONCLUSIONS The results suggest that smoking increases the lowering effect of alcohol drinking on LDL cholesterol, but does not affect the relationship of alcohol drinking with HDL cholesterol.