Abstract
Conjugated linoleic acid (CLA) has been shown to exert various physiological functions in experimental animals, and the mechanisms underlying the effects are being investigated. CLA is prepared from linoleic acid (e.g., safflower oil) by alkaline isomerization. The product is a 1 : 1 mixture of 9c, 11t-18 : 2 and 10t, 12c-18 : 2, and is commonly used for commercially available CLA. Physiological property of CLA differs between the two isomers; 9c, 11t-18 : 2 exhibits only limited functions such as anticarcinogenicity, whereas 10t, 12c-18 : 2 exhibits various functions including antiobesity. Although CLA, mostly as a 9c, 11t-isomer, is found in ruminant meats and dairy products, these foods are far from significant source of CLA due to very low content. The body fat reducing effect of 10t, 12c-18 : 2 is attractive in weight management in humans. For this reason, CLA supplement has already been commercially available. Also, foods supplemented with CLA are recently coming to the market. Thus, CLA is now entering its new stage as a functional food ingredient.
