Fish oil is the oil extracted from the tissues and belly cavities of certain species of fish considered to be oily fish. Some species include salmon, sardines, anchovies, trout, and mackerel. Fish oil is oil derived from the tissues of oily fish. Fish oils contain the omega-3 fatty acids eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), precursors of certain eicosanoids that are known to reduce inflammation throughout the body, and have other health benefits. Show More