what is tyrosine used for
â Tyrosine is a building block of protein. Itâs used by the body to build lean muscle, which is why many people take Tyrosine as a bodybuilding supplement. â Tyrosine can be used to treat the genetic disorder phenylketonuria, or PKU, which inhibits lean muscle growth.yrosine is an amino acid. Our bodies produce Tyrosine from another amino acid called phenylalanine. We can also intake Tyrosine directly from milk, eggs, fish, nuts, beans, wheat, oats, and most dairy products.