CLA is a naturally occurring trans isomer of linoleic acid. It is unique in structure because of the location of the double bonds in the linoleic acid molecule. Recent research shows that the specific isomers c9 t11 and t10 c12 play key roles in many of CLA s physiological properties. Tonalin CLA contains the main isomers c9 t11 and t10 c12 in a 39:39 ratio. Several animal studies explore possible mechanisms of CLA including the ability to maintain healthy deposition promote lipolysis in adipocytes moderate energy intake and maintain healthy energy expenditure and metabolic rate.