L-Tyrosine is a non-essential amino acid used by cells to synthesize proteins. It is synthesized in the body from L-phenylalanine, and is the building block for several brain chemicals. This amino acid can be found in casein, a phosphoprotein that accounts for 80 percent of the protein in milk and cheese. L-tyrosine is derived from the Greek word tyros, which means cheese. It is needed to make epinephrine, norepinephrine, serotonin, and dopamine, which are all used to elevate a person’s mood. When a person has an L-tyrosine deficiency, they are usually diagnosed with depression.

Functions of L-tyrosine include:

• Mood elevation
• Production of melanin, which is the pigment that gives your hair and skin its color
• Regulating hormones such as the adrenal, thyroid, and pituitary glands
• Involvement in the synthesis of substances that reduce pain in the body

Although it isn’t proven that L-tyrosine supplementation helps with these issues, those who have low levels of L-tyrosine in their system have been found to have low blood pressure, low body temperature and an underactive thyroid. While considered an amino acid, L-tyrosine is also a mild antioxidant since it helps bind unstable molecules known as free radicals. Free radicals are harmful oxygen molecules that cause damage to cells in the body.

L-tyrosine is used for the following conditions:

• Phenylketonuria—this illness occurs in those who can’t metabolize phenylalanine. When people can’t metabolize that amino acid it can lead to mental retardation or other types of brain damage. The main treatment is to reduce the patient’s intake of phenylalanine, which can lead to an L-tyrosine deficiency since L-tyrosine is made from phenylalanine.
• Stress—research shows that L-tyrosine can act as an adaptogen, which helps users cope with their situations and reduces anxiety and depression.
• Vitiligo—sufferers have skin discoloration manifested as white patches of skin. Since L-tyrosine is involved in making melanin, which gives your skin and hair its color, some think it is beneficial to those with vitiligo.

Those taking L-tyrosine supplements are advised to take them three times a day and 30 minutes before meals.