Effect of fish oil on platelet kinetics in patients with ischaemic heart disease.

The effect of taking fish oil rich in eicosapentaenoic acid on platelet kinetics was studied in 13 patients with ischaemic heart disease. No other change in diet, medication, or smoking habits was permitted. The fish oil provided 3.5 g of eicosapentaenoic acid a day. After 5 weeks the fish oil caused a 10% lengthening in platelet survival time, a 15% fall in platelet count, a 75% fall in plasma levels of platelet factor 4, and a 30% fall in plasma-beta-thromboglobulin. These findings suggest that a diet rich in omega-3 polyunsaturated fatty acids, such as eicosapentaenoic acid, will reduce platelet/vessel-wall interaction and may reduce the risk of ischaemic heart disease. Long-term studies to explore the toxicity and alleged protective effects of fish oil are justified.