CLA Supplements: Burn Fat And Speed Recovery
Conjugated linoleic acid (CLA) is both a trans- and a cis- fatty acid that is found naturally occurring in small amounts in meat and dairy products. There are many different isomers of CLA, and of these isomers the two that are most abundant in CLA supplements are the cis-9, trans-11 isomer and the trans-10, cis-12 isomer. The claim of companies producing CLA supplements is that conjugated linoleic acid has a positive effect on body composition because it helps to both burn fat and build muscle. Additional supposed benefits of CLA supplementation are that it acts as an antioxidant and an anti-inflammatory. Most CLA supplements recommend 1 gram taken 1-3 times daily.
The current human research on CLA supplements has shown many benefits. They have been shown to reduce body fat, improve metabolism of fats, improved insulin sensitivity, act as an antioxidant, increase fat oxidation, inhibit lipogenesis (storage of calories as fat) and decrease inflammation. (1, 2, 3, 4, 5, 8, 6) Studies have also shown negative effects of mixed isomer CLA supplements like an increase in insulin sensitivity and a lowering of HDL cholesterol. (4)
The research seems to point to most of the positive effects coming from the cis-9, trans-11 isomer, while the benefits of the trans-10, cis-12 isomer are limited. The few negative effects that were experienced in human studies were possibly attributable to the trans-10, cis-12 isomer. The negative effects of this isomer include inflammation, an increase in insulin resistance, and an increase in oxidative stress. (7) This isomer of conjugated linoleic acid has, however, been found to have lipogenesis inhibiting effects (prevents storage of calories as fat) which the cis-9, trans-11 isomer does not possess. (8, 7)
As far as the real-world effectiveness of CLA supplements for improving body composition, the studies done on humans seem to be split as to whether or not CLA can actually make a significant difference. Its anti-lipogenesis and insulin sensitivity improving effects suggest that CLA may be worth adding into your supplement regimen during a bulk to limit fat gains, its antioxidant and anti-inflammatory effects suggest that it may improve recovery from training, and its ability to increase fat oxidation suggest that it may help you lose fat during a cutting phase. How significant these effects are is debatable, but CLA seems to be a good staple supplement to use every day of the year so that over time, its benefits in terms of body composition may become significant.
1. Baddini Feitoza A, Fernandes Pereira A, Ferreira da Costa N, & Gonçalves Ribeiro B. (2009). Conjugated linoleic acid (CLA): effect modulation of body composition and lipid profile. Nutrición Hospitalaria : Organo Oficial De La Sociedad Española De Nutrición Parenteral Y Enteral. 24(4), 422-8.
2. Lambert EV, Goedecke JH, Bluett K, Heggie K, Claassen A, Rae DE, West S, Dugas J, Dugas L, Meltzeri S, Charlton K, & Mohede I. (2007). Conjugated linoleic acid versus high-oleic acid sunflower oil: effects on energy metabolism, glucose tolerance, blood lipids, appetite and body composition in regularly exercising individuals. The British Journal of Nutrition. 97(5), 1001-11.
3. Colakoglu S, Colakoglu M, Taneli F, Cetinoz F, & Turkmen M. (2006). Cumulative effects of conjugated linoleic acid and exercise on endurance development, body composition, serum leptin and insulin levels. The Journal of Sports Medicine and Physical Fitness. 46(4), 570-7.
4. Salas-Salvadó J, Márquez-Sandoval F, & Bulló M. (2006). Conjugated linoleic acid intake in humans: a systematic review focusing on its effect on body composition, glucose, and lipid metabolism. Critical Reviews in Food Science and Nutrition. 46(6), 479-88.
5. Wang Y, & Jones PJ. (2004). Dietary conjugated linoleic acid and body composition. The American Journal of Clinical Nutrition. 79(6), 1153S-1158S.
6. Blankson H, Stakkestad JA, Fagertun H, Thom E, Wadstein J, & Gudmundsen O. (2000). Conjugated linoleic acid reduces body fat mass in overweight and obese humans. The Journal of Nutrition. 130(12), 2943-8.
7. Risérus U, Basu S, Jovinge S, Fredrikson GN, Arnlöv J, & Vessby B. (2002). Supplementation with conjugated linoleic acid causes isomer-dependent oxidative stress and elevated C-reactive protein: a potential link to fatty acid-induced insulin resistance. Circulation. 106(15), 1925-9.
8. Brown JM, Halvorsen YD, Lea-Currie YR, Geigerman C, & McIntosh M. (2001). Trans-10, cis-12, but not cis-9, trans-11, conjugated linoleic acid attenuates lipogenesis in primary cultures of stromal vascular cells from human adipose tissue. The Journal of Nutrition. 131(9), 2316-21.