Effects of ethanol on bile acid and cholesterol metabolism

The effects of ethanol on plasma lipid and lipoprotein concentrations and on the fecal excretion of neutral sterols and bile acids were studied in three patients with ethanol-induced hyperlipidemia and in four normolipidemic men. In the three patients, plasma triglyceride and cholesterol concentrations were much higher with ethanol than during periods when ethanol was isocalorically substituted with either carbohydrate or both fat and carbohydrate. In the normolipidemic subjects, plasma lipids especially in very low density lipoproteins, were higher with ethanol consumption only in comparison with a balanced diet but not when compared with carbohydrate-rich diets. Triglyceride enrichment of low density lipoproteins occurred uniformly with ethanol. Total sterol excretion, measured by isotope dilution and chemical assay, was similar during ethanol and control periods in two out of the three hyperlipidemic subjects. However, the proportion of bile acids was increased in all three hyperlipidemic subjects but in only one normolipidemic subject while on ethanol. Since cholesterol turnover did not appear to be necessarily influenced by ethanol, as judged either by total endogenous sterol excretion or from the slope of the plasma cholesterol specific radioactivity-time curve, the ethanol-induced increase in bile acid excretion amy not be analogous to other clinical disorders in which increased bile acid excretion and hypertriglyceridemia are associated with raised sterol production.