essential fatty acid(redirected from Fatty acids, essential)
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es·sen·tial fat·ty ac·id
a fatty acid that is nutritionally essential; for example, linoleic acid, linolenic acid.
essential fatty acid (EFA)
a polyunsaturated acid, such as linoleic, alpha-linolenic, and arachidonic acids, essential in the diet for proper growth, maintenance, and functioning of the body. EFAs are prostaglandin precursors that play important roles in metabolism. They are also necessary for the normal functioning of the reproductive and endocrine systems and the breaking up of cholesterol deposits on arterial walls. The best dietary sources are natural vegetable oils, such as soy and corn oils; margarines blended with vegetable oils; wheat germ; edible seeds, such as pumpkin, sesame, and sunflower; and fish oils, especially cod liver and other fish body oil. Although rare, a deficiency of EFAs causes changes in cell structure and enzyme function, resulting in decreased growth and other disorders. Symptoms include brittle and lusterless hair, nail problems, dandruff, allergic conditions, and dermatoses, especially eczema in infants. Also excessive amounts may reduce the level of vitamin E in tissues and cause other metabolic disturbances.
essential fatty acidBiochemistry
A fatty acid that humans cannot synthesise, which contains double bonds more distal than the COOH end of the 9th carbon atom:
(1) Linoleic acid 18:2 cis-delta 9, delta 12, which has two unsaturated carbon bonds; the first is attached at the methyl end to the 6th carbon (hence, n-6 or omega-6); and
(2) Linolenic acid 18:3 cis-delta 9, delta 12, delta 15.
Some practitioners of alternative healthcare believe cystic fibrosis and ADD/ADHD in children may respond to an increased dietary intake of EFAs.
es·sen·tial fat·ty ac·id(EFA) (ĕ-sen'chăl fat'ē as'id)
The 18-carbon fatty acids that are nutritionally required by humans and must be consumed through dietary sources. The EFAs are linoleic acid or C18:2 (n-6) and alpha-linolenic acid or C18:2 (n-3).