By Ross Edgley, BSc Sports Science

Daily supplementation of Conjugated Linoleic Acid (CLA) may reduce body fat and favorably change body composition researchers at I-Shou University in China reveal.   The study led by Chih-Kun Huang, MD took 63 subjects and randomly assigned them to receive daily supplements of CLA (3.4 grams) or a placebo (salad oil) in a milk product for 12 weeks. Results showed that after 12 weeks of supplementation participants in the CLA group displayed average decreases in bodyweight of 0.7kg, BMI of 0.31 kg/m2, body fat mass of 0.58kg and fat percentage of 0.6%. Chih-Kun Huang said ‘to our knowledge this is the first randomized, double-blinded, placebo-controlled clinical trial to evaluate the effect of CLA on body fat composition and the results seem promising.’ Concluding ‘the consumption of milk supplemented with CLA (3.4 grams per day) significantly decreased the body weight, BMI, body fat mass, fat percentage, subcutaneous fat mass and the waist-to-hip ratio in subjects over just 12 weeks.’

But what exactly is conjugated linoleic acid and what are the benefits for athletes, bodybuilders or gym goers? Well it’s a naturally occurring fatty acid found mainly in cheese and beef however it’s only found in these foods in very low doses (no way near the 3.4 grams used in the study at I-Shou University previously mentioned). Furthermore similar promising results were found at Uppsala University in Sweden where they found supplementing 4.2 grams of CLA a day in healthy, young subjects resulted in a 3.8% decrease in body fat compared with individuals not taking the supplement.

Whilst it’s clear studies support the use of CLA to lower your body fat, experts still aren’t entirely clear as to the mechanism by which it works. It’s been theorized that it reduces your body fat in 3 ways: firstly research conducted at the University of País Vasco found that conjugated linoleic acid interferes with a substance in your body called lipoprotein lipase, which aside from various other roles in the body is mainly responsible for storing fat in the body. Furthermore Simón. E et al 2005 of the same study found that CLA actually helped the body use its existing fat for energy. Therefore studies show CLA not only inhibits the storing of fat it also enhances the burning of fat.

Thirdly, and perhaps most important for athletes, bodybuilders or those training for aesthetics, it was found CLA supplementation actually increased muscle mass as well as lowering body fat. This in turn increases your basal metabolic rate and the amount of calories you burn at rest. Scientists concluded therefore that CLA doesn’t actually make you lose weight (like thermogenics do) but rather it favorably changes your body composition (i.e. body fat to muscle ratio). This notion is further supported by the 1 year human study published in the American Journal of Clinical Nutrition that found CLA supplementation produced a 9% reduction in body fat and 2% increase in muscle mass.

So in summation, CLA supplementation may prove effective for athletes wanting to change their body composition (such as American Football players wanting to get rid of unwanted fat and develop a more powerful and ‘functional’ physique) but perhaps not so effective for athletes wanting to lower their weight such as boxers, martial artists or anyone athletes needing to make a weight cut. Regarding dosage, there seems to be different amounts that have proved effective in various studies ranging from 1.4 grams to 6.5 grams. The most common dosage seems to be 3 grams per day, so it may be advisable to start with this dosage and increase or decrease depending on how your body responds.

 

About the Author: Ross Edgley is a Sports Scientist with a BSc Degree in Sports Science from Loughborough University. Ross Edgley was a Strength and Conditioning Coach at The English Institute of Sport working alongside Britain’s Olympic Physicians, Nutritionists and S&C coaches and is currently fitness and nutrition advisor to a range of athletes and the UK’s biggest online sports nutrition company Myprotein.com.

 

References:

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Berven G, Bye A, Hals O, Blankson H, Fagertun H, Thom E,Wadstein J, Gudmundsen O. Safety of conjugated linoleic acid (CLA) in overweight or obese human volunteers. European J. Lipid Sci.Technol. 102:455;462 (2000).

Thom E,Wadstein J, Gudmundson O. Conjugated linoleic acid reduces body fat in healthy exercising humans. J Int Med Res 2001;29:392-6.

Kamphuis MMJW, Lejeune MPGM, Saris WHM, Westerterp-Plantinga MS. The effect of conjugated linoleic acid supplementation after weight loss on body weight regain, body composition, and resting metabolic rate in overweight subjects. Int J Obesity 2003; 27: 840-847.

Gaullier Jm, Hasle J,Hoye K., Kristiansen K., Berven G., Blankson H and Gudmonson O. Effects of CLA in moderate overweights during one year supplementation. 94th AOCS annual meeting and Expo, Kansas,May 2003

A. Zabala et al (2006) ‘Trans-10,cis-12 Conjugated linoleic acid inhibits lipoprotein lipase but increases the activity of lipogenic enzymes in adipose tissue from hamsters fed an atherogenic diet.’ Br J Nutr. 2006 Jun;95(6):1112-9.