BACKGROUND: Epidemiological studies suggest an unclear effect of alcohol consumption on cardiovascular risk. This ambiguity is likely related to the quantity of alcohol consumed in populations studied. The aim of this work was to evaluate the association between chronic alcohol consumption and several clinical and biochemical parameters related to coronary risk, in cardiovascular disease free men and women. METHODS: The 'ATTICA' study is a population-based cohort, which randomly enrolled 750 men and 883 women (18-88 years old) from area around Athens, during 2001-2002. We investigated the association between alcohol consumption and arterial blood pressure, fibrinogen levels, glucose concentration, total cholesterol, HDL and LDL, apolipoprotein A1 and B, Lp(a), uric acid, leucocyte count, triglycerides, C-reactive protein and homocysteine levels. RESULTS: Multivariate analysis, after controlling for several potential confounders, revealed a J-shaped association between alcohol intake (none, 1-2, 3-4, 5+ wine glasses/day) and uric acid, C-reactive protein, homocysteine, fibrinogen, triglycerides, apolipoproteins A1 and B, HDL and total cholesterols, blood glucose levels, leucocyte count and arterial blood pressure levels (only in males). The most beneficial values of all these biochemical and clinical parameters were found in alcohol intake of 100-200 ml (12% alcohol), even after adjustment for various potential confounders. CONCLUSIONS: The controversial association between alcohol intake and cardiovascular disease seems to be partially explained by the J-shaped relation of several biochemical parameters related to atherosclerosis and the amount of alcoholic beverages consumed.