We reviewed the use of marine-derived omega-3 fatty acids in cardiovascular disease by discussing key epidemiologic and placebo-controlled studies in people with and without prior cardiovascular disease at baseline. In addition, studies on the antitriglyceridemic, antihypertensive, hemostatic, antiarrhythmic, and antiatherogenic properties of omega-3 fatty acids were examined. Lastly, we discussed current dietary and safety recommendations regarding fish and fish oil capsules as stated by the US Food and Drug Administration and the US Environmental Protection Agency.

We found that omega-3 fatty acids have shown to significantly reduce coronary mortality and sudden death in people without prior cardiovascular disease and reduce all-cause death and cardiac mortality in secondary prevention studies. Studies on stroke are still unclear and more studies need to focus on stroke subtypes.

The beneficial effects of omega-3 fatty acids might be the result of their ability to reduce triglyceride levels, blood pressure, platelet aggregation, arrhythmia, and atherogenesis.

Currently, the general public is recommended to consume two fatty fish meals per week (0.3-0.5 grams per day eicosapentaenoic acid and docosahexaenoic acid). Pregnant mothers and children should refrain from eating fish high in methylmercury levels while limiting their consumption of other fish varieties to 12 ounces per week. Patients with coronary heart disease should have 1 g per day of eicosapentaenoic acid and docosahexaenoic acid, whereas patients with hypertriglyceridemia should take 3 to 5 g per day of eicosapentaenoic acid and docosahexaenoic acid under a physician's supervision.