A type of polyunsaturated fat believed to have multiple health benefits. Omega-3 fatty acids get their name from the structure of their molecules, in which the first of several double bonds occurs three carbon atoms away from the end of the carbon chain. There are three types of omega-3 fatty acids: Alpha-linolenic acid (LNA) is found in vegetable sources, and eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) come from fish and other marine life.
Research has suggested that consuming omega-3 fatty acids found in fish and fish oils could protect a person from coronary heart disease. For example, some studies have shown that Greenland Eskimos, who consume a lot of seal and whale meat, have much lower blood cholesterol levels, lower triglyceride levels, and lower rates of coronary artery disease than people living in Denmark (who consume less fish). Other studies have shown that men who ate fish at least once a week had a lower mortality rate from coronary artery disease than men who ate none.
Other potential benefits of omega-3 fatty acids have also emerged from scientific studies, including the following:
• Diets rich in omega-3 fatty acids may decrease insulin resistance in people with diabetes.
• Those who consume more fish appear to have lower rates of depression, and omega-3 supplements, when used in conjunction with conventional medical therapy, may be helpful in treating bipolar disorder (also known as manic depression) and schizophrenia.
• Omega-3 supplements have been shown to improve symptoms of inflammatory diseases such as asthma, rheumatoid arthritis, lupus, and inflammatory bowel disease.
Health experts agree that it is generally a good idea for most people (with or without diabetes) to consume more omega-3 fatty acids in their diet. The richest dietary source of omega-3 fatty acids is oily cold-water fish such as salmon, sardines, mackerel, and herring. Omega-3 fatty acids can also be found in nuts (especially walnuts), flaxseeds, canola oil, and specially fortified eggs.
Taking fish oil supplements may also be helpful, but you should take them in addition to — rather than instead of — getting omega-3 fatty acids from your diet and following your diabetes treatment plan. Studies have shown that fish oil supplements may lower triglyceride levels in people with Type 2 diabetes, which could lower their risk of heart disease. However, fish oil supplements may, in some people, significantly raise the levels of low-density lipoprotein (LDL), the so-called “bad” cholesterol. People taking them should have their blood lipid levels monitored regularly. In addition, since fish oil supplements can affect blood clotting, people who are taking anticlotting medicines, have had a hemorrhagic stroke, or are having surgery in the near future should avoid them.