By: Dr. Sean Hashmi

If you have spent any time in the fitness arena, then you have surely heard about Branched Chain Amino Acids (BCAAs). Chances are you may have even been using them for some time. In the gym, people rave about the tremendous benefits of BCAA’s. They claim it can promote weight loss, enhance athletic performance and improve recovery. So is it all hype or is there any truth behind their popularity.  Let’s look at the research behind BCAA’s and draw our own conclusions.

So what are BCAA’s? BCAA’s are 3 of the nine essential amino acids in humans. They consist of leucine, isoleucine, and valine.  What makes them so unique is that they make up a very large portion of our muscles. In fact, they account for over one-third of the amino acids in muscle protein.  Out of the 3 BCAA’s, leucine is considered by many to be the most important.  Now before you go rushing for a bottle of BCAA’s, realize that you can get them from eating a nice balanced diet. High concentration of leucine can be found in foods such as beans, eggs, nuts, seeds, soy, whey and whole grains.  Isoleucine is also present in fish, dairy, meats, eggs, nuts and soy protein. Finally, valine can be found in meats, soy, dairy, and nuts.  Bottom line here is that a diet composed of lean meats, dairy products and nuts provides a good source of BCAA’s. Athletes may require supplementation to meet higher demands.

Now let’s turn our attention to the data and see what well designed research studies tell us.  In a small, randomized, double-blind, placebo controlled study, Matsumoto and colleagues looked at taking BCAA’s and their effects on muscle soreness and muscle damage. They measured plasma creatinine kinase (CK), lactate dehydrogenase (LDH) and granulocyte elastase (GEL). These are all markers elevated in muscle damage. The results were quite impressive. The people taking BCAA had a 21 percent reduction in plasma CK, a 6 percent reduction in LDH, and a 15 percent reduction in GEL. All of these reductions were statistically significant. A number of other well designed studies have shown similar results.

In a recent study, Sharp and Pearson took the role BCAA further by looking at testosterone and cortisol levels along with creatinine kinase levels. Using a randomized, placebo control design, they had participants perform high-intensity total-body resistance training. Their findings were in line with previous studies showing lower markers of inflammation (cortisol) and damage (CK). In addition, they also showed that athletes supplementing with BCAA group had significantly higher serum testosterone levels.

In terms of weight loss, there is some interesting data. A nice review by Devkota and Layman showed that supplementing with 2.5 grams of Leucine allows for increased fat loss during dieting while protecting lean muscle mass.  However, Cheng and colleagues showed that mice maintained on a leucine poor diet experienced greater fat loss.  Pedrosa and colleagues showed that supplementing with Leucine did not result in increased fat loss.  So the jury is still out on BCAA’s for weight loss.

The beneficial effects of BCAA’s extend far beyond those of muscle recovery for athletes. A review of 11 randomized studies showed that BCAA supplementation improved worsening of brain function (hepatic encephalopathy) seen in patients with liver damage. In addition, studies have also shown in rat models that BCAA supplementation promotes glucose uptake by cells. Finally, BCAA’s have been shown to stimulate appetite and improve nutrition status in both the elderly and patients on hemodialysis.

So there you have it, the scientific research supporting BCAA for muscle recovery. Go ahead and eat that chicken breast, the egg white omelet, or a variety of delicious foods high in BCAA’s. Your taste buds will be happy and your muscles will thank you.

References:

• -Matsumoto K, et al. Branched-chain amino acid supplementation attenuates muscle soreness, muscle damage and inflammation during an intensive training program. J Sports Med Phys Fitness. 2009 Dec;49(4):424-31.
• -Sharp CP, Pearson DR. Amino acid supplements and recovery from high-intensity resistance training. J Strength Cond Res. 2010 Apr;24(4):1125-30.
• -Glyn El, et al. Excess leucine intake enhances muscle anabolic signaling but not net protein anabolism in young men and women. J Nutr 2010 Nov;140(11):1970-6. Epub 2010 Sep 15.
• -Lee IJ, et al. Effect of Oral Supplementation with Branched-chain Amino Acid (BCAA) during Radiotherapy in Patients with Hepatocellular Carcinoma: A Double-Blind Randomized Study. Cancer Res Treat. 2011 Mar;43(1):24-31. Epub 2011 Mar 31.
• -Nishitani S, et al. Branched-chain amino acids improve glucose metabolism in rats with liver cirrhosis. Am J Physiol Gastrointest Liver Physiol 288:G1292-G1300, 2005.
• -Devkota S, Layman DK. (Commentary). Curr Opin Clin Nutr Met Care. 2010;13:403-407.
• -Pedrosa RG et al. Leucine supplementation favors liver protein status but does not reduce body fat in rats during 1 week of food restriction. Appl Physiol Nutr Metab. 2010 Apr;35(2):180-3.
• -Cheng Y, et al. Leucine deprivation decreases fat mass by stimulation of lipolysis in white adipose tissue and upregulation of uncoupling protein 1 (UCP1) in brown adipose tissue. Diabetes. 2010 Jan;59(1):17-25. Epub 2009 Oct 15.