omega-3 fatty acid

Omega-3 fatty acids are a family of polyunsaturated fatty acids which have in common a carbon-carbon double bond in the ω-3 position. (See Nomenclature for terms and discussion of ω (omega) nomenclature.)Important nutritional essential omega-3 fatty acids are: α-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). For a more complete list see List of omega-3 fatty acids. The human body cannot synthesize omega-3 fatty acids de novo, but it can form 20- and 22-carbon unsaturated omega-3 fatty acids from the eighteen-carbon omega-3 fatty acid, α-linolenic acid. These conversions occur competitively with omega-6 fatty acids, which are essential closely related chemical analogues that are derived from linoleic acid. Both the omega-3 α-linolenic acid and omega-6 linoleic acid are essential nutrients which must be obtained from food. Synthesis of the longer omega-3 fatty acids from linolenic acid within the body is competitively slowed by the omega-6 analogues. Thus accumulation of long-chain omega-3 fatty acids in tissues is more effective when they are obtained directly from food or when competing amounts of omega-6 analogs do not greatly exceed the amounts of omega-3.
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Noun
1. a polyunsaturated fatty acid whose carbon chain has its first double valence bond three carbons from the beginning
(synonym) omega-3
(hypernym) polyunsaturated fatty acid
(hyponym) alpha-linolenic acid

A type of fat obtained in the diet and involved in immunity.