Effect on Blood Lipids and Haemostasis of a Supplement of Cod-Liver Oil, Rich in Eicosapentaenoic and Docosahexaenoic Acids, in Healthy Young Men

Abstract

The polyunsaturated fatty acids found in fatty fish may help prevent coronary heart disease. Twelve healthy male [human] subjects took a daily supplement of 20 ml of cod-liver oil for 6 wk. This provided 1.8 g of eicosapentaenoic acid (20:5.omega.3) and 2.2 of docosahexaenoic acid (22:6.omega.3). The effects of the supplement on blood lipids, hemostatic variables, bleeding time and plasma vitamin A and carotene were studied. In 7 subjects platelet aggregation induced by ADP was also studied. The proportions of 20:5.omega.3 and 22:6.omega.3 in platelet and erythrocyte phosphoglycerides were substantially increased by the supplement mainly at the expense of .omega.6 polyunsaturated fatty acids. Mean plasma triglyceride concentrations were reduced and those of high-density-lipoprotein (HDL) cholesterol were increased by the supplement. The mean bleeding time was significantly prolonged after 3 wk of taking the supplement but had returned to the presupplementation value 5 wk after withdrawal of the supplement. The maximum estimated response to platelet aggregation induced by ADP was increased by the supplement. The mean levels of antithrombin III (immunological) and blood pressure were lower at the end of the period of supplementation and remained so 5 wk after withdrawal of the supplement. No significant changes in other variables were noted.