Effects of Chronic Ethanol and Fish Oil on Plasma and Liver Lipids and Plasma Apoproteins

Abstract

A number of studies have shown that inclusion of polyunsaturated fatty acids in the diet has a marked hypolipidemic effect. Most of these studies have utilized highly polyunsaturated vegetable oils such as corn oil or safflower oil which belong to the w-6 family. Fish oils which are very rich in w-3 polyunsaturated fatty acids have been shown to have pronounced hypolipidemic effects (2,6,7,8,24,26). The members of the w-6 and w-3 family are considered to be essential fatty acids for mammals because they cannot synthesize these fatty acids de novo (1). The metabolic differences between dietary fish oils and vegetable oils have been examined only recently (7,8,24). Harris et al. (7) have found that both types of polyunsaturated fat diets reduce plasma total cholesterol and low density lipoproteins (LDL) cholesterol, but only the fish oil diet significantly reduces the triglyceride and very low density lipoproteins (VLDL) levels. Neither diet has any significant effect on the plasma high density lipoproteins (HDL) cholesterol concentration (7). On a unit weight basis, the w-3 fatty acids have a greater hypocholesterolemic effect than the w-6 fatty acids. Furthermore, the hypotriglyceridemic effect seems to be unique to w-3 fatty acids.