Effects of Dietary Supplementation with n‐6 and n‐3 Long‐chain Polyunsaturated Fatty Acids on Serum Lipoproteins and Platelet Function in Hypertriglyceridaemic Patients

Abstract
Twenty-seven patients with hypertriglyceridaemia were given dietary supplementation either with evening primrose oil rich in gammalinolenic acid (GLA, 18:3 n-6) (n=13) or a marine oil concentrate containing n-3 fatty acids (n=14) in a double-blind cross-over design during 8+8 weeks with olive oil as placebo. During GLA supplementation, increases in GLA and dihomogammalinolenic acid (20:3 n-6) were found in plasma lipid esters and platelet phospholipids, whereas platelet function and serum lipoproteins were unaffected. During supplementation with n-3 fatty acids there was a significant decrease in triglycerides in all lipoprotein fractions with a slight increase in high density lipoprotein and low density lipoprotein cholesterol. A marked increase in the long-chain n-3 fatty acids was found both in plasma and platelets, mainly at the expense of the n-6 fatty acids. No pronounced effects on platelet reactivity could be demonstrated. Our results confirm a triglyceride-lowering effect of n-3 fatty acids, whereas no such effect of GLA could be demonstrated.