Effects of a moderate dose of alcohol on blood lipids and lipoproteins were studied in volunteers of two age groups (20-30 and 45-55 years), each consisting of eight healthy men. The alcohol (30 g in red port and wine) was consumed during a standard dinner. Two blood samples were drawn: one in the postprandial phase, and one the next morning after fasting overnight. In the postprandial phase, one hour after intake, alcohol increased high-density lipoprotein cholesterol (HDL-C) by 11.5%, triglycerides (TG) by 15.3% and apolipoprotein A2 (Apo-A2) by 7.3% (P = 0.002, P = 0.044 and P = 0.024, respectively). The increase in HDL-C appeared to be mainly attributed to the HDL2-C subfraction which increased by 15.3% (P = 0.066). Furthermore, the increases in HDL-C, HDL2-C and TG were more pronounced in the middle-aged men then in the young men. After fasting overnight the effects of alcohol had disappeared.