Omega-9

Omega-9 fatty acids (ω−9 fatty acids or n−9 fatty acids) are a family of unsaturated fatty acids which have in common a final carbon–carbon double bond in the omega−9 position; that is, the ninth bond from the methyl end of the fatty acid.

Some omega−9 fatty acids are common components of animal fat and vegetable oil. Avocado oil is 70% Omega-9 fatty acid by percentage, giving it the highest smoke point of all vegetable oils. Two omega−9 fatty acids important in industry are:

Unlike omega-3 fatty acids and omega-6 fatty acid, omega−9 fatty acids are not classed as essential fatty acids (EFA). This is both because they can be created by the human body from unsaturated fat, and are therefore not essential in the diet, and because the lack of an omega−6 double bond keeps them from participating in the reactions that form the eicosanoids.

Under severe conditions of EFA deprivation, mammals will elongate and desaturate oleic acid to make mead acid, (20:3, n−9). This has been documented to a lesser extent in one study following vegetarians and semi-vegetarians who followed diets without substantial sources of EFA.

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