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Nutrition & Supplements: Branched Chain Amino Acids – Katie Weaver

The use of branch chain amino acids (BCAA) in use is becoming more prevalent in recent years as supplement manufactures begin to advertise more aggressively toward specific populations such as athletes and young adults. The major concern with this practice is that the individuals consuming this supplement others are not well informed on the risks assumed when they begin supplementation. Furthermore most drug companies are uninterested in educating the public on what they are consuming and in what quantities.  Many individuals just conform to traditional thoughts on supplementation, which can be a dangerous practice to abide by considering the new information we obtain everyday on supplement usage especially among athletes and the devastating effects that can occur when used improperly.


The human body though in most cases can fend for itself and overcome extreme challenges has eight essential amino acids which cannot be produced by the body alone but must be obtained from an outside source. The most common way to acquire theses essential proteins specifically BCAA is through ingesting food such as meats, dairy, and legumes which are foods such as beans, peas, and lentils. The proteins in these foods are broken down into a simpler form creating the amino acids. Specifically BCAA are three of the eight essential amino acids leucine, isoleucine, and valine. They are given the term branched because of the unique chemical structure of these three amino acids that give them a branched appearance contrasting most other amino acids that have a more linear structure (Buse, 1997).


In the medical world BCAA are used for the treatment of several aliments. Patients with liver cirrhosis have proven to benefit from a BCAA enriched diet. Other medical condition that have scientifically verified gain from excess ingestion of BCAA include improving muscle control in those with compromised muscle function due to trauma, aide in the recovery of burn victims, and reducing muscle breakdown during exercise. The reduction of muscle breakdown leads athletes to believe that this can enhance athletic performance, however like many issues related to sports nutrition and supplementation there is too little viable literature on the subject. Studies are extremely hard to conduct because of the increased number of variables in athletes such as type of sport, type of environment (open versus closed) and unmonitored eating habits. This is just a small list of possible variables affecting the ability to study the true effects of supplements.


The misconception about BCAA is derived from the idea that athletes need to consume large amounts of proteins to build muscle which in fact has no scientific backing. Therefore since amino acids compose proteins theoretically taking in excessive BCAA will make you build more muscle and increase strength. This idea has been extrapolated by drug companies who look to profit off of these types of products. More recent studies have shown that the misuse of BCAA can lead to serious health issues when used over an extended period of time. Side effects of this supplement include fatigue, loss of coordination, and low blood sugar; all of which seems to be the exact opposite of the athlete’s goals.

The recommended daily allowance (RDA) of BCAA is easily obtainable through a healthy diet. Daily intake of BCAA for adults is between 70-140 mg/kg/day with a 2:1:1 ratio of leucine, isoleucine, and valine respectively.  Consequently even if you are consuming the highest recommended allowance of 140 mg/kg/day you would only need about 70 mg/kg/day of leucine and 35 mg/kg/day of isoleucine and valine each.( Kasparek, 1987) Compared to other nutrients essential for the body to function BCAA have very low intake requirements.  There is not current standing recommendation for supplementing BCAA with the exception of treating preexisting conditions. Medical circumstances warranting excess BCAA intake include but are not limited to brain swelling, anorexia nervosa, and Tardive Dyskinesia.

Production of BCAA supplements are not regulated by the FDA. This means that the amount of each ingredient listed on the label is not congruent in each bottle. Supplements unapproved by the FDA also have not been tested for adverse side effects in labs not associated with the company producing the supplement. This is important because the involved companies have money and time invested in these products which can unfortunately often time sway the results of the labs findings.

Research in the field of athletics and nutrition is fairly inconclusive in most cases. Studies involving BCAA are included in this statement. Many explorations of BCAA are not related to athletic performance but rather to the treatment of disease where supplementation of amino acids has proven to be a useful resource. This is not surprising considering the level of difficulty associated with research conducted in a closed environment with controlled patients versus studies involving open environment (i.e. sports fields) with athletes whom all variables can’t possibly be controlled. The few studies that have been completed concluded that BCAA supplementation does not have a positive effect on overall athletic performance.  Data reported showed that a placebo has similar results to the BCAA supplement.

However, there is evidence that BCAA interaction with the physiology of the body is extensive and shows many benefits such as increased speed if muscles repair and recovery during the post exercise stage.

Several articles support this finding; therefore BCAA supplementation may be useful during intense long duration exercise. One particularly interesting study was conducted during a marathon run in Stockholm. One hundred and ninety-three male were randomly split into groups and half were given BCAA mixed into water while the others were just given plain water. The subjects were also categorized as “slow runners “and “quick runners” defined by whether they finished in the top fifty percent or bottom fifty percent of the race. The data concluded that the runners with the BCAA enriched water were able to replenish muscle glycogen stores and repair damaged muscle quicker. However significant results were only recorded in only the slow runners. Therefore you would conclude that physiology and genetics has a great impact on BCAA supplementation. Participants with a higher VO2max or individuals finishing the race first are able to restore glycogen levels quicker than those with a lower VO2max(Madsen, 1997). Although this study has some very intriguing results some of the methods of gathering data has been criticized. All other research was largely inconclusive or very poorly conducted.

 Other research has also found that if the supplements are taken in very large amounts by healthy individual it can have very detrimental effects. These effects can be both short-term and long-term. More long term effects include liver and kidney damage. The damage is done to filtering organs because of the extra strain put on them by trying to get the overload of amino acids out of the system. Most athletes would not overuse supplements to this degree however weight lifters, wrestlers, and sports emphasizing strength and size to a high degree are at risk for over supplementation.

Athletes should take caution when starting and supplementation and should consult with their athletic trainer, coach, or doctor before beginning supplement usage. Branch chain amino acid at this point with the current research completed show that they should never be used as an exercise supplement. The intake of BCAA must be closely monitored to be ingested in safe amounts. The risks of BCAA supplementation to enhance exercise clearly out way the benefits. As a professional working with athletes it’s important to be observant and open with your athletes about what is safe and what it hazardous to their health. You should know where to refer you athletes if you don’t have answers or feel uncomfortable either for ethical or legal reasons giving your opinion. The most important factor in athletics is prevention of injury which includes the negative effect of supplementation. There will never be a magic pill that increases your muscle mass and strength; hard work and healthy diet are the best way to improve body composition and performance.  So beware of marketing scams that propose incredible results. If it sounds too good to be true it probably is. Also keep in mind that money will make people say anything, so you cannot trust your favorite professional athlete to steer you in the right direction when it comes to supplementation. The bottom line is do your research and know what you are going to put into your body; it’s worth your time.


Work Cited:

Buse MG & Reid SS.Leucine. A possible regulator of protein turnover in muscle.J. Clin. Invest1995; 56: 125061.

Daly JN, Mihranian M, Kehoe J, Brennan M.Effects of postoperative infusion of branched chain amino acids on nitrogen balance and forearm muscle substrate flux.Surgery1983; 94: 1518.

Gelfand RA, Glickman MG, Jacob R, Sherwin RS, DeFronzo RA.Removal of infused amino acids by splanchnic and leg tissues in humans.Am. J. Physiol1986; 250: E40713.

J. J. Hulmi, J. Tannerstedt, H. Selanne, H. Kainulainen, V. Kovanen, and A. A. Mero. Resistance exercise with whey protein ingestion affects mTOR signaling pathway and myostatin in men, J Appl Physiol, May 1, 2009; 106(5): 1720 – 1729.

Kasparek G & Snider R.Effect of exercise intensity and starvation on activation of branched chain keto acid dehydrogenase by exercise.Am. J. Physiol.1987; 252: E337.

L. Cynober and R. A. Harris. Can You Buy Valium In Australia Symposium on Branched-Chain Amino Acids: Conference Summary, J. Nutr., January 1, 2006; 136(1): 333S – 336S.

M. Beelen, R. Koopman, A. P. Gijsen, H. Vandereyt, A. K. Kies, H. Kuipers, W. H. M. Saris, and L. J. C. van Loon Buy Phentermine Tablets 37.5 . Protein coingestion stimulates muscle protein synthesis during resistance-type exercise, Am J Physiol Endocrinol Metab, July 1, 2008; 295(1): E70 – E77.

M. J. Drummond, M. Miyazaki, H. C. Dreyer, B. Pennings, S. Dhanani, E. Volpi, K. A. Esser, and B. B. Rasmussen. Expression of growth-related genes in young and older human skeletal muscle following an acute stimulation of protein synthesis, J Appl Physiol, April 1, 2009; 106(4): 1403 – 1411.

Madsen K, MacLean DA, Kiens B, Christensen D.Effects of glucose, glucose plus branched-chain amino acids, or placebo on bike performance over 100 km.J. Appl. Physiol1996; 81: 264450.

Tandan R, Bromberg MB, Forshew Det al. A controlled trial of amino acid therapy in amyotrophic lateral sclerosis: I. Clinical, functional, and maximum isometric torque data.Neurology1996; 47: 12206.

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