Objective: To evaluate the effect of moderate alcohol consumption on the acute phase proteins C-reactive protein and fibrinogen. Design: Randomized, diet-controlled, cross-over study. Setting: The study was performed at TNO Nutrition and Food Research, Zeist, The Netherlands. Subjects: Ten middle-aged men and 10 postmenopausal women, all apparently healthy, non-smoking and moderate alcohol drinkers, were included. One women dropped out because of a treatment-unrelated cause. The remaining 19 subjects finished the experiment successfully. Interventions: Men consumed four glasses and women consumed three glasses of beer or no-alcohol beer (control) with evening dinner during two successive periods of 3 weeks. The total diet was supplied to the subjects and had essentially the same composition during these 6 weeks. Before each treatment there was a 1 week washout period to compensate for possible carry-over effects. Results: Plasma C-reactive protein and fibrinogen levels were decreased by 35% (P = 0.02) and 12.4% (P ≤ 0.001), respectively, after 3 weeks' consumption of beer, as compared to no-alcohol beer consumption. Conclusions: Moderate alcohol consumption significantly decreased plasma C-reactive protein and fibrinogen levels. An anti-inflammatory action of alcohol may help explain the link between moderate alcohol consumption and lower cardiovascular disease risk.