Linoleic acid is an unsaturated fatty acid. Linoleic acid (LA) is a naturally occurring fatty acid found in beef ,dairy products and oils like safflower and soy oil, . Linoleic acid is one of the two essential fatty acids (the other is linolenic acid). Linoleic acid is an omega-6 fatty acid, meaning that it is unsaturated, with a double bond occurring at the sixth carbon atom from the omega end of the molecule.

Linoleic acid-- CH ₃ (CH₂)₄CH=CHCH2CH=CH(CH₂)₇COOH ,

Conjugated linoleic acid (CLA) is a mixture of positional and geometric isomers of linoleic acid, which is found preferentially in dairy products and meat. Preliminary studies indicate that CLA is a powerful anticancer agent in the rat breast tumor model with an effective range of 0.1-1% in the diet. While linoleic acid is found in the diet in vegetable oils, the conjugated variety, CLA, is found primarily in meat and dairy products.

Conjugated linoleic acid is unique because it is present in food from animal sources, and its anticancer efficacy is expressed at concentrations close to human consumption levels. See:Conjugated linoleic acid and atherosclerosis in rabbits Lee K.N.; Kritchevsky D.; Pariza M.W. Food Research Institute, Dept. Food Microbiology/Toxicology, University of Wisconsin-Madison, 1925 Willow Drive, Madison, WI 53706 USA Atherosclerosis (Ireland), 1994, 108/1 (19-25)