There is epidemiological evidence that a moderate consumption of alcohol could reduce coronary heart disease. To corroborate this statement and to see how the consumption of red wine affects phospholipid and fatty acid patterns and antioxidant status, a survey was conducted on 58 adult males (20-75 years old). A questionnaire was used to discover their medical history, various constitutional and life-style factors, food habits, and nutrient intake; and the type and amount of alcoholic intake were investigated by means of a questionnaire. Subjects were divided into two groups of nondrinkers and average drinkers (mean 46.5 +/- 4.4, range 30.2-63.4 g/day), and the effect of alcohol was made on the following variables: gamma-glutamyltranspeptidase, apolipoprotein AI, apolipoprotein B, total and high-density lipoprotein-cholesterol, triglycerides, and antioxidant vitamins were determined in plasma; and phospholipids the fatty acids of phosphatidylcholine (PC) and phosphatidylethanolamine total cholesterol, alpha-tocopherol, beta-carotene, and retinol were determined in red blood cells (RBCs). There were no significant differences between the two groups in protein, fat, carbohydrate, retinol equivalent, alpha-tocopherol content, and cholesterol/saturated fat index of their diet. Analysis of the plasma levels of biochemical variables--adjusted for age, smoking (number of cigarettes/day), and body mass index--showed a significant increase of gamma-glutamyltranspeptidase and apolipoprotein AI concentration in the average drinkers compared with nondrinkers. Plasma alpha-tocopherol and retinol levels were also significantly higher in average drinkers. In the latter group, ANCOVA demonstrated a lower percentage of sphingomyelin in RBCs, with a lower sphingomyelin/PC ratio.(ABSTRACT TRUNCATED AT 250 WORDS)