The effect of cessation and resumption of moderate alcohol intake on serum high-density-lipoprotein subfractions. A controlled study.

High-density lipoproteins (HDL) in plasma may be divided into two subfractions: less dense HDL2, the concentration of which appears to be negatively associated with coronary heart disease, and more dense HDL3, which is reportedly unrelated to coronary disease. Alcohol consumption correlates with both reduced coronary heart disease and increased plasma HDL cholesterol concentrations; however, the relation of moderate alcohol intake to HDL2 and HDL3 is obscure. To study the effect of alcohol on these HDL subfractions, we randomly assigned 24 men who were moderate drinkers to an abstention group (n = 12) or a control drinking group (n = 12). After six weeks, concentrations of HDL cholesterol and HDL3 mass were decreased in abstainers but not in drinkers (P less than or equal to 0.05), whereas HDL2 mass was unchanged. Resumption of drinking increased the levels of HDL cholesterol and HDL3 mass (P less than or equal to 0.05) without affecting HDL2 mass. These data suggest that the association of alcohol with coronary disease is not mediated by increases in plasma HDL2 levels. Furthermore, the HDL3 fraction may not be "inert" with respect to coronary heart disease, or the association of alcohol with coronary disease may operate through mechanisms unrelated to HDL.