Omega-3 fatty acids are one of the two types of polyunsaturated fats. The other type is omega-6 fatty acids. The main dietary source of omega-3 fatty acids are soybean and canola oils, with flaxseed oil being an especially rich source. The dietary sources for omega-6 fatty acids are vegetable oils, such as corn, safflower, and soybean. A long chain omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are found in seafood, with oily fish such as salmon, mackerel, herring, and sardines being particularly good soruces.
Health Benefits of Omege-3 fatty acids
- Cardiovascular Diseases. Lowers risk of heart attacks 
- Hypertrygleceridemia. EPA plus DHA can produce a 45% reduction in serum triglyceride level 
- Obstetrics. There is limited evidence to suggest that omega-3 fatty acids and fish oil may lower pre-term birth. Women with increased intake of fish had birth weights about 200gm higher and a gestation 3-4 days longer than those with lower intake 
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