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.

Inclusion criteria

• BMI 25-29.9 kg/m2
• Absence of a weight change of greater than 3 kg in the previous 6 months

Exclusion criteria

• Presence of a physical limitation to walking exercise
• Current or recent (6 months) enrollment in a commercial or self-prescribed weight loss program
• A history of metabolic disease-ie. renal, endocrine, hepatic or gastrointestinal disease that would impact the outcome of the study
• A history of a psychiatric or eating disorders Ÿ Presence of metal implants that would interfere with body composition analysis
• Fasting plasma cholesterol >300mg/dl or triglycerides above 500 mg/dl.
• Abnormal EKG