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CLA (conjugated linoleic acid)

Linoleic acid is an important component of biolipids, and comprises a significant proportion of triglycerides and phospholipids. Linoleic acid is known as an essential fatty acid, meaning that the animal must obtain it from exogenous dietary sources since it cannot be autosynthesized.  Conjugated linoleic acid (CLA) is a mixture of positional and configurational isomers of octadecadienoic acid, which are naturally occurring substances found in milk and diary products as well as in meats of ruminants. Conjugated linoleic acid (CLA) has two conjugated double bonds between the ninth and the twelfth carbons or between the tenth and thirteenth carbons, with possible cis and trans combinations. Conjugated double bonds means two or more double bonds which alternate in an unsaturated compound as in 1,3 butadiene. The hydrogen atoms are on the same side of the molecule in the case of cis. The hydrogen atoms are on the opposite side of the molecule in the case of trans. Conjugated linoleic acid comprises a group of positional and geometric isomers of linoleic acid in which various configurations of cis and trans double bonds at positions (6,8), (7,9), (8,10), (9,11), (10,12) or (11,13) are possible. Thus, twenty-four different isomers of CLA exist. Conjugated linoleic acid occurs naturally in ruminant depot fats. The predominant form of CLA in ruminant fat is the cis,trans-9,11-octadecadienoic acid which is synthesized from linoleic acid in the rumen by micro-organisms like Butryvibrio fibrisolvens. Conjugated linoleic acid has a significant potency relative to other fatty acids with respect to modulating tumorigenesis. CLA is closely related to linoleic acid but differs from linoleic acid in the position and configuration of the double bonds. Linoleic acid has a stimulatory effect on carcinogenesis, as contrasted with the ability of conjugated linoleic acid to inhibit tumor development. In this way, conjugated linoleic acid has the opposite effect of linoleic acid in treating carcinomas. In fact, conjugated linoleic acid has a significant potency relative to other fatty acids in modulating tumorigenesis. Conjugated linoleic acid has become the focus of numerous research programs which seek to capitalize on its nutritional, therapeutic, and pharmacologic properties. It has been discovered that conjugated linoleic acid (CLA) possesses beneficial effects for humans. For example, CLA is known to help reduce body fat and to enhance or maintain protein levels in humans. It is also known to prevent the weight loss that is associated with immune stimulation. In addition, there is research that suggests that it may be useful for other purposes. The ingestion of conjugated fatty acids may inhibit tumor growth, prevent heart disease, and reduce body fat. There is a great deal of interest in the apparent health benefits imparted by certain conjugated linoleic acids. CLA has been incorporated into the diet in liquid, gel or powdered forms, though the preferred method of administration is generally oral. The CLA has also been formulated with suitable carriers such as starch, sucrose or lactose in tablets, capsules, solutions and emulsions. Conjugated linoleic acid preparations are also provided as supplements in various prepared food products.

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