Contains 500mg of L-Tyrosine to help support adequate intake Holland & Barrett L-Tyrosine is a non-essential amino acid which means it can be produced by the body as well as obtained through the diet. Foods such as Soya, Chicken and Beef are good sources of Tyrosine. In some individuals the quantity of Tyrosine needed can be greater than the amount that can be produced by the body or consumed in the diet, this is where a L-Tyrosine supplement may be needed. Amino Acids are the building blocks of protein. Protein makes up the structure of all cells and tissues in the body, including muscle tissue, tendons, internal organs, skin, hair and nails. There are 20 amino acids, 12 of these can be made by the body and are referred to as non-essential whilst the other 8 are known as essential and can only be supplied by the diet. Contains 500mg of L-Tyrosine to help support adequate intake Holland & Barrett L-Tyrosine is a non-essential amino acid which means it can be produced by the body as well as obtained through the diet. Foods such as Soya, Chicken and Beef are good sources of Tyrosine. In some individuals the quantity of Tyrosine needed can be greater than the amount that can be produced by the body or consumed in the diet, this is where a L-Tyrosine supplement may be needed. Amino Acids are the building blocks of protein. Protein makes up the structure of all cells and tissues in the body, including muscle tissue, tendons, internal organs, skin, hair and nails. There are 20 amino acids, 12 of these can be made by the body and are referred to as non-essential whilst the other 8 are known as essential and can only be supplied by the diet.