Omega-3 Fatty Acids

Omega-3 fatty acid is an essential fatty acid as the body cannot synthesize it and it should be supplied by external dietary sources. Three main kinds of omega-3 fatty acids are – alpha-linolenic acid, docosahexanoic acid and eicosapentaenoic acid. Food sources of alpha-linolenic acid are flaxseeds, green leafy vegetables, and various other vegetables. Food source of docosahexanoic acid (DHA) and eicosapentaenoic acid (EPA) are oily cold water fish like sardines, salmon, mackerel, bluefish, halibut and herring. Omega-3 fatty acid is also found in buffalo, walnuts and venison.

Commercially available fish oil in capsule form is also a good source of omega-3 fatty acids.

Currently there are no specific dietary guidelines drawn for omega-3 fatty acids consumption and recommendation, however a range of 1.1 to 1.6 gm has been established per day for adults (flaxseed provide 1.6 gm of omega-3 fatty acid per tablespoon). According to American Heart Association one should not exceed the oily fish consumption beyond three serving per week. This conclusion is made by the scientists after studying various fishes and the level of metal contamination (mercury, lead), pesticides and toxins in them. As in the process of gaining benefits from omega-3, these contaminants may adversely affect one’s health.

EPA and DHA when consumed from dietary omega-3 fish oil or fish oil supplements help to decrease triglycerides, total cholesterol and lower blood pressure, thus reducing the risk of heart attack, abnormal heart rhythm, cardiovascular diseases, blood clots and stroke. Omega-3 fatty acids may also improve mood swings and mental health; decreases join pain, inflammation, stiffness and swelling. Thus is beneficial for patients with arthritis or other inflammatory conditions. It may also help to prevent and relieve cancer symptoms.

Omega-3 fatty acids from fish is generally regarded safe, however if taken in high doses it may pose health risks like increased risk of bleeding, hemorrhagic stroke, low glycemic control in diabetes, increased risk of forming biologically active oxidative products due to oxidation, decreased resistance to infection due to suppression of immune system and inflammatory responses. Along with omega-3 fatty acids fish oil also contains substantial amounts of other fat soluble fatty acid like vitamin E, A and D (fish oil when taken for many months can cause vitamin E deficiency), thus can sometimes cause toxicity of vitamin A and D.

Before taking any nutritional supplement of omega-3 fatty acid or containing capsules with fish oil, it is recommended to do so under the guidance and supervision of a health care professional as omega-3 fatty acid may also interact with some drugs, herbal or dietary supplements.

Submitted on January 16, 2014