The present study was done to evaluate the effects of conjugated linoleic acid (CLA) on body composition and on blood tests for the metabolic syndrome. Previously CLA been shown to be anti-carcinogenic, protective against arteriosclerosis, immune stimulating and a modulator of body composition. CLA is found in ruminant products such as beef, lamb, milk, and cheese, but recent dietary changes have reduced our intake of CLA.
In a study of sixty men and women with symptoms of the metabolic syndrome, weight, waist circumference and body mass index were measured. Metabolic syndrome required abnormalities of at least two of the following: Elevated systolic blood pressure, diastolic blood pressure, elevated blood glucose or low HDL-cholesterol.
The subjects of the twelve week study were given 500 mg. of milk, daily, supplemented with either placebo or 3 g. CLA. At the conclusion of the study there was significant change in the fat mass in the overweight patients but not in the obese patients. Although there were changes in body composition, there were no changes seen in other parameters related to the metabolic syndrome such as blood glucose, blood pressure and insulin sensitivity.
CONCLUSION: CLA (3 g.) supplementation of milk resulted in a loss of fat mass in overweight but not in obese patients when given daily for twelve weeks. There was no change in the parameters of metabolic syndrome with CLA supplementation. No toxic effects of CLA were found and CLA appears to be beneficial in reducing body fat mass, which is a risk factor for cardiovascular disease.
NOTE: What dietary changes have resulted in a deficient intake of CLA? One of the major differences is in the way the animals, which provide much of our food supply, are fed. Long term grain fed cows have higher total fat, saturated and monounsaturated fatty acids. Grass fed animals have higher levels of omega-3, DHA and EPA. Feeding animals flax seed, fish extracts and algae (oil) increases the quality of the animal as food for humans.