L-tyrosine, or tyrosine, is a nonessential amino acid. This means that it can be synthesized by the body from phenylalanine. Tyrosine plays an important role in the thyroid, nervous system, and skin.
Tyrosine is an important input in the production of neurotransmitters; most notably dopamine and norepinephrine.
Because of its role in the synthesis of neurotransmitters, tyrosine is thought to be beneficial for people suffering from mood disorders, Parkinson’s, Alzheimer’s, and depression.