Branched-chain amino acids (BCAAs) are essential amino acids that cannot be synthesized by humans and therefore must be included as part of one’s diet.

There are three BCAAs – leucine, isoleucine and valine – that together make up about one-third of all skeletal muscle in the body.

BCAAs are metabolized by B-group vitamins, such as vitamin B6, and they play an important role in protein synthesis. Because of this, BCAAs are used medically to assist in the recovery of burn injuries and in the fitness world as strength supplements.