Fish Oil and Heart Health

Large controlled trials have shown that intake of fish oil (marine n-3 fatty acids, eicosapentaenoic acid, and docosahexaenoic acid), whether from dietary sources or fish oil supplements, may exhibit beneficial effects on total and cardiovascular disease mortality. Stabilization of cell membranes and suppression of cardiac arrhythmias have been identified as possible mechanisms. Moreover, n-3 fatty acids have anti-inflammatory effects, reduce blood pressure, and may also be antiatherogenic. Finally, high doses of n-3 fatty acids can lower elevated serum triglyceride levels. The n-3 index (erythrocyte eicosapentaenoic acid plus docosahexaenoic acid) may be considered as a potential risk marker for coronary heart disease mortality, especially sudden cardiac death. The balance of n-6 to n-3 fatty acids is an important determinant in decreasing the risk for coronary heart disease, both in the primary and in the secondary prevention of coronary heart disease. Patients with known coronary heart disease should be recommended to consume n-3 fatty acid supplements at 1 g per day, without raising concerns for interactions with other medications or side effects. On the other hand, fish in the diet (preferably oily fish, 1-2 meals/week) should be considered as part of a healthy diet low in saturated fat.