Essential fatty acid

Essential fatty acids, or EFAs, are fatty acids that humans and other animals must ingest because the body requires them for good health,^{[clarification needed]} but cannot synthesize them.^[1]^[2]

Only two fatty acids are known to be essential for humans: alpha-linolenic acid (an omega-3 fatty acid) and linoleic acid (an omega-6 fatty acid). These are supplied to the body either as the free fatty acid, or more commonly as some glyceride derivative.^[3] Deficiency in these fatty acids is rare. These fatty acids are essential because they are precursors to vitamins, cofactors, and derivatives, including prostaglandins, leukotrienes, thromboxanes, lipoxins, and others.^[4]

When the two EFAs were discovered in 1923, they were designated "vitamin F", but in 1929, research on rats showed that the two EFAs are better classified as fats rather than vitamins.^[5]

^ Robert S. Goodhart; Maurice E. Shils (1980). Modern Nutrition in Health and Disease (6th ed.). Philadelphia: Lea and Febinger. pp. 134–138. ISBN 978-0-8121-0645-9.
^ Essential fatty acids should not be confused with essential oils, which are "essential" in the sense of being a concentrated essence. Some other fatty acids are sometimes classified as "conditionally essential", meaning that they can become essential under some developmental or disease conditions; examples include docosahexaenoic acid (an omega-3 fatty acid) and gamma-linolenic acid (an omega-6 fatty acid).
^ Whitney Ellie; Rolfes SR (2008). Understanding Nutrition (11th ed.). California: Thomson Wadsworth. p. 154.
^ Cite error: The named reference Das was invoked but never defined (see the help page).
^ Burr, G.O., Burr, M.M. and Miller, E. (1931). "On the nature and role of the fatty acids essential in nutrition". J. Biol. Chem. 86 (587): 587–621. doi:10.1016/S0021-9258(20)78929-5.{{cite journal}}: CS1 maint: multiple names: authors list (link)

[1] Robert S. Goodhart; Maurice E. Shils (1980). Modern Nutrition in Health and Disease (6th ed.). Philadelphia: Lea and Febinger. pp. 134–138. ISBN 978-0-8121-0645-9.

[2] Essential fatty acids should not be confused with essential oils, which are "essential" in the sense of being a concentrated essence. Some other fatty acids are sometimes classified as "conditionally essential", meaning that they can become essential under some developmental or disease conditions; examples include docosahexaenoic acid (an omega-3 fatty acid) and gamma-linolenic acid (an omega-6 fatty acid).

[3] Whitney Ellie; Rolfes SR (2008). Understanding Nutrition (11th ed.). California: Thomson Wadsworth. p. 154.

[Das-4] Cite error: The named reference Das was invoked but never defined (see the help page).

[Burr-5] Burr, G.O., Burr, M.M. and Miller, E. (1931). "On the nature and role of the fatty acids essential in nutrition". J. Biol. Chem. 86 (587): 587–621. doi:10.1016/S0021-9258(20)78929-5.{{cite journal}}: CS1 maint: multiple names: authors list (link)

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