Branched-Chain Amino Acids: Effects, Risks and Uses.

Branched chain amino acids (BCAAs) are a common nutritional supplement peddled by sport nutrition stores and professional bodybuilders alike. While these amino acids do have numerous positive effects – the ones we’ll be talking about here, the “what-s, how-s, when-s and why-s” of this supplement are rarely discussed beyond “it’ll help build muscle bro!”.

So, we decided to give you a well-informed article about what BCAAs are, how to use them, when to use them, and, most importantly, why to use them in the first place!


The what: explaining what BCAAs are.

Amino acids are the building blocks of proteins. Proteins are the building blocks of the human body. There are different groups of amino acids in our bodies but we can artificially split them up into 3 groups:

  • Essential amino acids (EAAs): These are the amino acids we absolutely need to consume in our diets. They are not made by our bodies and are necessary for its normal functioning. These include: histidine, leucine, isoleucine, methionine, phenylalanine, threonine, lysine, tryptophan and valine.
  • Non-essential amino acids: We consume these as well with our food, but unlike EAAs, they can also be synthesized by our bodies.
  • Conditional amino acids: These are not usually essential but may become essential under stressful situations such as illness, starvation or extreme exercise.

Where do BCAAs fit into this? There are only 3 branched-chain amino acids and, unsurprisingly, all of them are essential. These include leucine, isoleucine and valine. The name of these amino acids comes from the fact that their chemical structures contain chains which branch off in different segments.


The how: how do BCAAs work? 

BCAAS make up a significant portion of the amino acids in the human body. Their importance is particularly high in our muscular tissues. It’s not surprising that exercise requires energy. Muscles have numerous ways of storing and utilizing this energy – they store carbs as glycogen, ATP as phosphocreatine (we talk about the importance of creatine in a separate article), and when all these other methods are exhausted muscles may use BCAAs.

Branched-chain amino acids are utilized by muscles to reduce the breakdown of glycogen and phosphocreatine. By allowing for these other energetic molecules to last longer, BCAAs contribute to endurance and may guard against fatigue during exercise.

The liver also maintains a large pool of BCAAs to use. When blood sugar is scarce the liver may use these amino acids to conserve the glucose left in the blood for the brain and muscles.


The when: when and how to use BCAA supplements?

Firstly, it is important to establish if you actually need to take BCAAs. The World Health Organization (WHO) states that a healthy adult should consume at least 34 mg/per kilogram of their body weight. However, newer research points to higher numbers being needed to keep up a healthy metabolism.

Most adults receive adequate amounts of BCAAs by consuming foods like meats, beans and lentils and other protein-laden products. An average person does not really need to consume additional BCAA supplements to maintain good health.

Athletes are a different picture entirely, the amounts of BCAAs they utilize and need are not found in a regular diet. An average athlete might be using as much as 15-20 grams of these amino acid supplements per day.

As for the timing – there is no real consensus. Most people use supplements just before or after a workout, while others prefer to take them in the morning and just before bed. There are no studies which support either method.


The why: why should I use BCAA supplements?

There are a large variety of positive effects to be had with BCAA supplements, including:

  • Less fatigue during exercise – physical endurance testing has shown improvement with BCAA supplementation.
  • Reduction of muscle pain/soreness – BCAAs conserve muscle glycogen and thus reduce lactic acid levels in these cells, causing a decrease in exercise-related pain.
  • May help increase muscle mass – while research on this topic is still in the early stages, athletes who use BCAAs swear by their ability to enhance hypertrophy.
  • May help with weight loss – BCAAs have a positive and non-placebo effect on weight loss. Study participants who received supplements were less likely to put on excess weight.

While the positive effects are convincing, it is also important to ask about the adverse effects these supplements may have. BCAAs do not usually produce any serious effects bar allergic reactions and stomach upset. In very rare cases taking these supplements is completely out of the picture. People with Amyotrophic Lateral Sclerosis (ALS, Lou Gehrig disease) should not consume any BCAA supplement products. The same warning goes out to people with the rare genetic disease called maple syrup urine disease.

Branched-chain amino acids are a safe and effective supplement for those who intend to work out on a regular basis or are involved in professional sports. The bottom line about these supplements being the following: if you’re an average joe – you could try using these and see if they work for you, if you’re an athlete – they are a must.