SANTIAGO, CHILE. Fish oils are excellent sources of EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). EPA and DHA in turn are important components of cell membranes and as such play a vital role in overall health. Studies have shown that Greenland Eskimos, who have a very high intake of oily fish, have a very low incidence of heart attacks, asthma, diabetes, psoriasis, and allergies. A Dutch study found that middle-aged men who ate as little as 30 grams of fish per day (average) reduced heart disease mortality by 50 per cent. A study at the Harvard Medical School concluded that men who eat fish have a 26 per cent lower risk of death from coronary artery disease than men who do not eat fish. Other studies have shown that an adequate DHA supply is essential for normal eye and brain development in infants and children.
Fish oils are found in high concentrations in herrings, sardines and anchovies, in medium concentrations in salmon, and in somewhat lower concentrations in sole, halibut, cod and shellfish. Oils from fish have demonstrable benefits in the prevention and treatment of cardiovascular disease; they reduce blood pressure and triglycerides, modify platelet aggregation, and minimize inflammatory responses. There is anecdotal evidence that fish oils may be beneficial in the treatment of migraine headaches, asthma, and psoriasis. Cell membranes rich in polyunsaturated fatty acids such as EPA and DHA are, however, more susceptible to peroxidation by free radical reactions. This may severely affect their structure and function unless precautions are taken to ensure that the free radicals are neutralized by lipid-soluble antioxidants. Research has shown that people taking fish oil supplements also need to increase their intake of vitamin E.
Uauy-Dagach, Ricardo and Valenzuela, Alfonso. Marine oils: the health benefits of n-3 fatty acids. Nutrition Reviews, Vol. 54, November 1996, pp. S102-S108