Several recent studies have shown that the supplement CLA can reduce body fat in animals and humans. Exercise has a similar effect but few studies have examined the interactive effects of both exercise and CLA supplementation on body composition. This study published last month in the Journal of Nutrition examined the effects of 14 weeks of CLA supplementation alone and in combination with exercise on body composition and associated mechanisms of action in mice. Similar to other studies, CLA resulted in a significant decrease in body fat. Exercise alone also resulted in a significant decrease in body fat. The combination of CLA and exercise led to largest reduction in body fat and a significant increase in lean body mass. CLA also resulted in a reduced inflammatory response to exercise and led to a more favorable metabolic and hormonal profile. The authors encourage short and long-term studies in athletes to determine whether CLA should be part of optimal sport nutrition strategies.

Bhattacharya A, Rahman MM, Sun D, Lawrence R, Mejia W, McCarter R, O'Shea M, Fernandes G. The combination of dietary conjugated linoleic acid and treadmill exercise lowers gain in body fat mass and enhances lean body mass in high fat-fed male Balb/C mice. J Nutr. 2005 May;135(5):1124-30.