[Specific effect of highly unsaturated lipids of animal origin on the blood lipid composition (author's transl)]

A beneficial effect, consisting in reduction of the risk of ischaemic cardiovascular disease, has long been attributed to fish lipids. These fish lipids were previously believed to be capable of markedly reducing the cholesterol level of the serum. However, recent studies showed that this reduction did not occur in normal subjects not affected with hypercholesteraemia, to whom fatty fish or polyunsaturated fatty acids isolated from fish were administered. On the other hand, the triglyceride level of the serum did decrease on administration of relatively large doses of these fatty acids. Moreover, the ingestion of fish lipids caused a shift in the fatty acid pattern of the serum lipids in the sense that w6 fatty acids were partially substituted for polyunsaturated fatty acids of the w3 type. This may result in changes in the synthesis of prostaglandins, which affect platelet aggregation and the bleeding time. This may indeed reduce the hazard of ischaemic cardiovascular disease.