L-tyrosine is a nonessential organic amino acid that is a building block of protein. It is an organic amino acid due to the presence of a carbon atom in its makeup.
It is a precursor of the neurotransmitter dopamine, as well as a precursor to the adrenal hormones nor-epinephrine and epinephrine. The body can make L-tyrosine from the amino acid phenylalanine. L-tyrosine rich foods include animal meat, wheat products, oatmeal and seafood.
Use in the Body:
L-tyrosine may help athletes avoid overtraining, due to its ability to offset fatigue. Because L-tyrosine is a precursor of dopamine, supplementing with L-tyrosine may heighten mental alertness, increase feelings of well being, and offset physical and mental fatigue.
Populations in need of L-tyrosine include: athletes, the obese or overweight, and the elderly. Hard training athletes may benefit from supplementing with L-tyrosine as it helps to offset fatigue and stress associated with intense training. L-tyrosine also serves to protect the integrity of the skin. Melanin, a substance which acts to protect the skin when the epidermis has been exposed to ultraviolet light, is derived from L-tyrosine. If a shortage of melanin is present within the body [because of a lack of L-tyrosine], skin defenses will be compromised. Melanin, which is derived from L-tyrosine, chemically reacts with sunlight to form a protective shield that protects the deeper layers of skin tissue.
Because persons suffering from depression frequently have low blood levels of this amino-acid, it may prove beneficial for members of this population to supplement with L-Tyrosine. Members of the obese population may benefit from supplemental L-tyrosine use due to L-tyrosine influencing the manufacture of thyroxin [T-cells], which influence basal metabolic rate.