There have been several epidemiological studies which support the fact that individuals at risk for cardiovascular and heart disease benefit from the consumption of plant omega-3s (alpha linolenic acid—ALA), and fish-derived omega-3 fatty acids (especially EPA and DHA). There are numerous mechanisms by which these omega-3 oils help prevent heart and blood vessel disease, including:
1. Decrease dangerous ventricular arrhythmias (heartbeat irregularities), especially fatal arrthymias
2. Prevent blood clotting
3. Lower triglycerides
4. Slow the production and growth of atherosclerotic calcium plaques (hardening arteries)
5. Prevent overall inflammation, which damages blood vessel lining (endothelium)
6. Promote nitric oxide-induced endothelial relaxation, which in turn…
7. Helps to lower blood pressure.
Prospective clinical studies have shown that the combination of EPA and DHA in the range of 500 mg to 1800 mg per day significantly reduces subsequent cardiac and all-cause mortality. For maximum benefit, it is also important to consider the omega-3 essential fatty acid linolenic acid (essential means it cannot be made by the body, and must be obtained from the diet or supplementation) which is the precursor for producing EPA and DHA in plants and fish. The beneficial intake is about 1500 mg to 3000 mg daily.
The above data supports the recommendation made by the AHA Dietary Guidelines to include at least two servings of fish per week and include plant-based oils from walnuts and flaxseeds, high in linolenic acid.1
However, due to environmental concerns of toxins in fish (PCBs in farm-raised fish, and mercury in wild fish), I think it is wise to consider getting most of your daily EPA and DHA from molecularly distilled fish oil, which is purified to remove these harmful toxins.
Since there can be issues with high doses of fish oil (most common is over-thinning of the blood), it would be a good idea to do a special blood test (annually) to determine the levels of all major oils in the red blood cell membranes. This test can be very valuable in determining whether you have too much, too little, or just the right amount of omega-3 and omega-6 oils, as well as the proper ratio of these oils. Keeping the balance right is key in preventing most illnesses, especially those due to inflammation, a factor involved in most all diseases.
P.M. Kris-Etherton, et al., “Fish consumption, fish oil, omega-3 fatty acids, and cardiovascular disease.” Circulation. 2002 Nov 19;106(21):2747-57.