Methionine is a protein amino acid, classified to the group of essential amino acids. The human body is not able to produce it by itself, therefore it should be delivered with food or in the form of a dietary supplement. Methionine is an important component of proteins, but also an irreplaceable donor of methyl groups. In addition, it acts as a substrate for the production of S-adenosylmethionine (SAMe) or glutathione.

Supplements with methionine can be used for both health and typically sports-related purposes. Methionine works well in chelation therapy aimed at detoxifying of the body from heavy metals. It can reduce copper toxicity and reduce the harmfulness of such compounds as paracetamol. By increasing the glutathione levels, methionine ensures a solid protection for the liver. As a donor of methyl groups, it affects many processes crucial for the proper functioning of the body, including the most important one, called methylation.

Methionine supplements are used by athletes primarily to improve regeneration and accelerate muscle growth. Researchers clearly point to the correlation between methionine supply and the pace of muscle mass development. Methionine is also used for the endogenous production of creatine, which has a huge impact on physical performance.