What to know about L-Tyrosine
L-tyrosine is a nonessential amino acid (protein building block) that the body synthesizes from phenylalanine, another amino acid. Tyrosine is important to the structure of almost all proteins in the body. It is also the precursor of several neurotransmitters, including L-dopa, dopamine, norepinephrine, and epinephrine.
Dairy products, meats, fish, wheat, oats, and most other protein-containing foods contain tyrosine.
Some people affected by PKU are deficient in tyrosine. Tyrosine levels are occasionally low in depressed people. Any person losing large amounts of protein, such as those with some kidney diseases, may be deficient in several amino acids, including tyrosine.
Stress Depression Phenylketonuria (for deficiency) Alcohol withdrawal support Parkinson’s disease
L-tyrosine has not been reported to cause any serious side effects. However, it is not known whether long-term use of L-tyrosine, particularly in large amounts (such as more than 1,000 mg per day) is safe. For that reason, long-term use of L-tyrosine should be monitored by a doctor. Vitamin B6, folic acid, and copper are necessary for conversion of L-tyrosine into neurotransmitters. Certain medicines may interact with L-tyrosine. Refer to drug interactions for a list of those medicines.
Most people should not supplement with L-tyrosine. Some human research with people suffering from a variety of conditions used 100 mg per 2.2 pounds of body weight, equivalent to about 7 grams per day for an average-sized person. The appropriate amount to use in people with PKU is not known, therefore, the monitoring of blood levels by a physician is recommended.