L-Glutamine amino acid powder: Protein makes up the structure of all cells and tissues in the body, including muscle tissue, internal organs, tendons, skin, hair and nails. Amino acids are the building blocks of protein and there are 20 of them. 12 of these can be made in the body and so are referred to as non-essential amino acids, while the other 8 are known as essential amino acids (as they must be sourced from the diet). Glutamine is a non-essential amino acid and is the most abundant free amino acid in muscle cells. This L-Glutamine food supplement is sourced from fermented glucose.