L-Methionine is an essential amino acid, which means that it cannot be manufactured by the body and must be obtained through the diet or by supplementation. L-Methionine supports the production of the cellular radical scavenger glutathione, and thereby assists in natural detoxification processes.

In the body, L-Methionine can also be converted into SAMe (S-Adenosyl Methionine), a compound that supports healthy joints.

Furthermore, the human body relies on ingested sulfur amino acids, such as L-Methionine, for the synthesis of protein, as well as for biologically active sulfur.