Polyunsaturated fatty acid

Polyunsaturated fatty acids (PUFAs) are fatty acids that contain more than one double bond in their backbone. This class includes many important compounds, such as essential fatty acids and those that give drying oils their characteristic property.

Polyunsaturated fatty acids can be classified in various groups by their chemical structure:

These fatty acids have 2 or more cis double bonds that are separated from each other by a single methylene bridge (-CH
2- unit). This form is also sometimes called a divinylmethane pattern.

The essential fatty acids are all omega-3 and -6 methylene-interrupted fatty acids. See more at Essential fatty acids—Nomenclature

Omega-3 fatty acids, polyunsaturated

Omega-6 fatty acids, polyunsaturated

Omega-9 fatty acids, mono- and polyunsaturated

Conjugated fatty acids have two or more conjugated double bonds

The biological effects of the ω-3 and ω-6 fatty acids are largely mediated by their mutual interactions, see Essential fatty acid interactions for detail.

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