L-Phenylalanine is an essential amino acid and is the only form of phenylalanine found in proteins ( Phenylalanine is found naturally in the breast milk of mammals. It is used in the manufacture of food and drink products and As a direct precursor to the neuromodulator phenethylamine, it is commonly used in dietary and nutritional supplement for its reputed analgesic and antidepressant effects. Phenylalanine is used for depression, attention deficit-hyperactivity disorder (ADHD),Parkinson's disease, chronic pain, osteoarthritis, rheumatoid arthritis.
Good sources of phenylalanine are eggs, chicken, liver, beef, milk, and soybeans. Other sources include spinach and leafy greens, tofu, amaranth leaves, and lupin seeds.
L-Phenylalanine is biologically converted into L-tyrosine, another one of the DNA-encoded amino acids. L-tyrosine in turn is converted into L-DOPA, which is further converted into dopamine, norepinephrine(noradrenaline), and epinephrine (adrenaline). The latter three are known as the catecholamines. Elevated brain levels of norepinephrine and dopamine are thought to have an antidepressant effect.
Phenylalanine should be avoided in people with certain inherited disorders that cause their bodies to build up too much phenylalanine. The genetic disorder phenylketonuria (PKU) is the inability to metabolize phenylalanine. People with this disorder should avoid consuming phenylalanine. Levodopa is used for Parkinson's disease. Taking phenylalanine along with levodopa can make Parkinson's disease worse. Do not take phenylalanine if you are taking levodopa.
Dosage: As a dietary supplement, take 1/4 level teaspoon daily, or as directed by a trained professional healthcare provider.