Ever been tempted by those bold brightly coloured tubs labelled ‘BCAAs’ flooding the supplement aisles?

BCAAs or Branched Chain Amino Acids have grown in popularity within the fitness industry of late and we’re here to divulge more on the current trend.

When we consume protein, our bodies break it down into amino acids which are used to carry out various bodily functions. There are 20 amino acids in total, 9 of which must be obtained from food and are known as essential amino acids (the other 11 occur naturally in the body). Six of the amino acids are used by the muscle tissue for energy. These include alanine, glutamate, aspartate and the branched chain amino acids (BCAAs). Out of these the BCAAs – valine, leucine and isoleucine – play the biggest role in energy use by the muscle and make up about a third of muscle protein1.

Leucine could be regarded as the most important BCAA when it comes to muscle growth. It promotes muscle synthesis and inhibits muscle degradation.

The intake of BCAAs has been shown to contribute to the enhancement of exercise performance due to its role in affecting fatigue, muscle and energy metabolism substances2.

In one study it was evaluated as to whether BCAAs play an important role in muscle mass in strength trained male participants3. The study group (36) was randomly divided into three groups – the first received 14 grams of BCAAs per day, the next received 28 grams of whey protein and the last 28 grams of carbohydrates in the form of an energy drink3. They focused on the strength training of various muscles, four days a week, for a total of eight weeks3. The participants all followed a standardized diet during the trial and their body weight, body composition, 10 rep-max on the bench press and squat were determined both before and after the eight-week training program3.

Overall, the group who were supplemented with BCAAs found a significant increase in body weight and lean mass compared to the other groups3. The group taking BCAAs found a greater decrease in overall body fat percentage and muscular strength was significantly increased3.

Studies show a variety of benefits to consuming BCAAs, not only for muscle growth but also reducing endurance fatigue while training1. The best part is that there is no need to supplement them as they’re found in foods that you’re more than likely consuming on a daily basis!

Food sources of BCAAs include, but are not limited to: whey and milk proteins, chicken, fish, soy proteins, eggs, brown rice, almonds, brazil nuts, pumpkin seeds, chickpeas, cashew nuts and lentils. The amounts we need are easily met through diet alone and consuming whole foods as opposed to supplements results in the consumption of a variety of other amino acids and essential nutrients. If consuming a balanced diet with lean sources of protein planning meals based on BCAA content isn’t necessary.

As previously stated, consuming BCAAs from a supplemental form is not superior to consuming whole-food sources. Taking them in the form of a powder added to water is an easy-on the go way to increase your BCAA intake however not essential.

When taking any supplement (not only BCAAs) it is important to consider:

  • Your current nutritional status: Eating a whole-foods balanced diet is what we should ultimately aim for. Consuming a variety of food sources ensures that we include the many different vitamins and minerals our bodies require thus eliminating the need to supplement.
  • Underlying medical conditions: These should be discussed with a medical professional based on your personal individualised needs (no one size fits all approach).

Written by: Nicole Keeling – Registered Dietitian, @cape.townfoods


1: Sowers, S. (2009). ‘A primer on branched-chain amino acids’. Huntington College of Health Sciences. Smart Supplementation.

2: Dong-Hee K et al. (2013). ‘Effect of BCAA intake during endurance exercises on fatigue substances, muscle damage substances, and energy metabolism substances’, The Journal of Exercise Nutrition & Biochemistry. 17(4):169-180.

3: Stoppani J, Scheett J, Pena J et al. (2009). ‘Consuming a supplement containing branched-chain amino acids during a resistance-training program increases lean mass, muscle strength and fat-loss’[Poster]. International Society of Sports Nutrition Conference and Expo.


  • Posted by KASHISH BAGGA on

    Thank you very much for sharing this great information about bcaas and other supplements. I was actually looking for natural foods with bcaa and other essential nutrients that I need so that I don’t need to take artificial supplements. This article helped a lot.

  • Posted by Inge Coetzee on

    Thank you for the informative read! You are super at your job and so professional Nicole.

Leave a comment