Branched chain amino acids (BCAA) have been a popular supplement for decades. It is estimated that the market size of BCAA supplements ranges from 200 million to 500 million US dollars, making it one of the best-selling supplements in the world. These supplements are usually positioned as muscle building supplements, or for individuals undergoing weight loss training, they are good tools for weight loss or maintaining lean weight.

What is BCAA?

BCAA includes leucine, isoleucine, and valine. It is an essential amino acid that the human body cannot synthesize on its own and can only be consumed through food or supplements

What are the benefits (is it beneficial for you?)


Leucine may be the most well-known of the three types of BCAA, as one of its main functions in the human body is to help promote muscle growth at the molecular level. Leucine has also been shown to stimulate the release of insulin from the pancreas. This helps to reduce muscle protein breakdown and increases glycogen storage. Promoting muscle protein synthesis and triggering insulin response means that consuming sufficient leucine after exercise can aid in recovery.


One recognized function of isoleucine is to increase the amount of glucose absorbed by muscle cells. Interestingly, it does not seem to stimulate glycogen synthesis like leucine, which may be due to a lack of insulin release or other mechanisms. This also indicates that consuming isoleucine together with leucine may be more effective than consuming either alone.


Valine is commonly considered as an auxiliary property of BCAA. This is mainly because the most well-known function of valine is its self conversion into glucose.

Do you need to supplement BCAA?

Most people already consume enough BCAA in their diet, so supplementing with BCAA will not bring any additional benefits. The most important consideration is leucine, as leucine has the strongest effect among the three BCAAs. Consuming approximately 3-10 grams of leucine per day will optimize muscle protein synthesis. This intake can be achieved through a comprehensive omnivorous diet or the use of high-quality protein supplements.

The population that can benefit from BCAA supplements includes:

  1. People who lose weight and consume a low calorie diet but need to maintain maximum lean muscle mass.
  2. Vegetarians have a lower protein content in their diet.
  3. Endurance athletes with high training volume and low protein diet.

Which foods have high BCAA content?

The food with the highest content in BCAA is often animal meat or animal by-products. For example, beef, poultry, fish, turkey, and eggs are good sources of BCAA, and dairy products such as cheese and milk also contain high levels of BCAA. Some plant-based foods, such as nuts, seeds, tofu, and lentils, contain an appropriate amount of BCAA.

Leucine, Isoleucine, and Valine are more effective when used in combination, so the BCAA currently available on the market is actually synthesized in a certain proportion of these three amino acids.