Moderate alcohol consumption is associated with lower cardiovascular mortality. The effect of moderate alcohol intake during 5 weeks on lipoproteins, especially on the high density lipoprotein (HDL) cholesterol total (of which the levels are inversely predictive of coronary heart disease) and apoproteins A, A1 and B, was studied in 7 normal men. HDL cholesterol total appreciated by the heparin manganese precipitation method and phosphortungstate magnesium method increased (p < 0.01) during alcohol consumption. The composition of HDL was modified by alcohol consumption: increase of the esterified/total cholesterol ratio (p < 0.05) and phospholipids (p < 0.05) without significant modification of triglycerides. Low density lipoprotein and very low density lipoprotein did not vary significantly. Apoprotein A1 increased during alcohol consumption (p < 0.05) with a transitory increase of apoprotein A. There was no significant modification of apoprotein B.