Omega-3 fish oils
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 in the body, and have other health benefits. Nonetheless, fish oil supplement studies have failed to support claims of preventing heart attacks or strokes.
Omega-3 fatty acids — also called ω-3 fatty acids or n-3 fatty acids — are polyunsaturated fatty acids (PUFAs) with a double bond (C=C) at the third carbon atom from the end of the carbon chain. The fatty acids have two ends, the carboxylic acid (-COOH) end, which is considered the beginning of the chain, thus “alpha”, and the methyl (CH3) end, which is considered the “tail” of the chain, thus “omega”. The way in which a fatty acid is named is determined by the location of the first double bond, counted from the methyl end, that is, the omega (ω-) or the n- end.