Conjugated Linoleic Acid (CLA)
Conjugated linoleic acid (CLA) is a polyunsaturated fatty acid found naturally in milk and meat and also produced from safflower and sunflower oils. It was discovered in Wisconsin and has been extensively researched there. Body builders are particularly interested in its effects of building lean muscle.
Mechanism of Action
CLA alters fatty acid synthesis and reduces body fat
Dose
3000 - 4000mg daily
Evidence
In a year long RCT, 180 overweight men and women (BMI 25 - 30) were allowed to follow any diet while taking one of two types of CLA or placebo. The CLA groups did not loose weight but had a lower body fat mass 8% (+/- 9%) compared to placebo (p< 0.001).
Adverse Effects
Nausea, gastrointestinal upset, loose stools (reduced if taken with protein). No adverse changes were seen in labs: chemistry, CBC, liver function, lipids, glucose or insulin.
Concerns have been raised for increasing cardiovascular risk with one study showing increases in fatty acid oxidation and negative effects on endothelial function.
May alter milk fat secretion so should not be used by women when breastfeeding.
Interpretation of Results So Far
CLA might be useful in the overweight group for maintaining their weight while reducing body fat mass. CLA should not be used during breastfeeding and may have cardiovascular risks.
References
Gaullier et al. Am J Clin Nutr. 2004 Jun;79(6):1118-25
Gaullier et al. J Nutr. 2005 Apr;135(4):778-84
Larsen et al. Am J Clin Nutr. 2006 Mar;83(3):606-12
Whigham et al. Food Chem Toxicol. 2004 Oct;42(10):1701-9
Taylor et al. Arterioscler Thromb Vasc Biol. 2006 Feb;26(2):307-12