special subjects
Fish Oil
What is fish oil?
Fish oilis derived from the tissues of oily fish, such as mackerel, herring, tuna, and salmon.Fish oilsupplements contain oil that is extracted directly or concentrated and put in capsule form. The active ingredients infish oilare omega-3 fatty acids (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]). Some plant-based foods, such as flaxseeds, chia seeds, walnuts, and canola oil, contain alpha-linolenic acid, which the body can convert to DHA and EPA. Also, yeast strains that can naturally produce substantial amounts of these oils have been genetically engineered. Western diets typically are low in omega-3 fatty acids. (See also Overview of Dietary Supplements .) 