Effects of CLA Supplements on Body Weight and Fat Oxidation

Subjects were screened and then underwent baseline evaluation. The substudy evaluation measured 24-h energy expenditure and substrate utilization by using a whole-room indirect calorimeter. Dietary fat oxidation was measured by mixing \[1-13C\]oleate and D31-palmitate into a breakfast meal and then collecting breath carbon dioxide and urine to measure the end products of oxidation. Subjects were then provided either 4 g/d of 78% active CLA isomers (3.2 g/d: 39.2% cis-9,trans-11 and 38.5% trans-10,cis-12) or 4 g/d of safflower oil placebo as 1-g gel capsule supplements. The baseline evaluations were repeated 6 mo later.