Lipoprotein metabolism and coffee intake--who is at risk?

Data from a representative health and nutrition survey of German adults (sample of 1073 women and 806 men) were used to investigate the relationship between coffee consumption and the concentration of cholesterol in serum as well as other lipoprotein constituents. For these outcome variables multivariate analyses were conducted separately for men and women. Differences in age, body mass index, smoking habits, use of oral contraceptives, physical activity, alcohol, fish, fat, milk and tea consumption were controlled for in the models. Interactions between coffee drinking behavior and smoking habits as well as between coffee and the use of oral contraceptives in their relationship with serum cholesterol were of special interest in the analyses. Higher coffee intake (> 400 ml/d) showed higher total cholesterol, LDL cholesterol and lower triglyceride rich lipoprotein (TRL) and triglyceride concentrations in serum compared to lower intake (< 200 ml/d). Smoking appeared to be an aggravating factor in these relationships. Results of the linear regression analysis demonstrated an increase of 1.66 mg/dL LDL-C per cup of coffee daily consumed for men and of 1.58 mg/dL for women. The combination of high coffee intake, smoking and no oral contraceptive use ever was associated with the highest total and LDL-C and lowest TRL concentrations in this population. The observed differences may be explained by an increase of lipoprotein lipase activity due to coffee consumption.