Essential amino acids

Essential amino acids (essential amino acids) are amino acids that a heterotrophic organism needs but cannot build itself from elementary components. If these amino acids are not part of the diet, the organism cannot survive in the long run.

Isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine are essential amino acids for humans. Arginine and histidine only need to be ingested with food in certain situations, such as adolescence or recovery, and are therefore called semi-essential.