Are trans fatty acids not essential and provide no known benefit to human health? The Wikipedia page for margarine has an unsourced line: > Unlike other dietary fats, trans fatty acids are not essential and provide no known benefit to human health. This seems like pretty bold claim to be completely unsourced. Are trans fats non-essential? Do they provide no known benefit to human health?

There's plenty of evidence showing that _manufactured_ trans fatty acids are harmful. However, Conjugated Linoleic Acid is a _naturally-occurring_ trans fat, which has several studies showing that it might have anti-cancer properties, as well as helping in weight management.

> ## Inhibition of carcinogenesis by conjugated linoleic acid: potential mechanisms of action.
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> Conjugated linoleic acid (CLA) is composed of positional and stereoisomers of octadecadienoate (18:2); it is found in foods derived from ruminants (beef and lamb as well as dairy products from these sources). When a mixture of isomers is fed to experimental animals, chemically induced tumorigenesis of mammary, skin and colon is reduced.
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> _J Nutr. 2002 Oct;132(10):2995-8._

Although CLA isn't an _essential_ nutrient, the OP actually made two claims, the other being about CLA having _no_ benefits.