L-phenylalanine

L-Phenylalanine is an essential amino acid. Inside the body, phenylalanine is converted into tyrosine, another amino acid. Tyrosine is then used to produce dopamine and norepinephrine, both neurotransmitters. All of these elements are important because of their relationship to the central nervous system.Phenylalanine is available in three chemical forms: L-phenylalanine, the natural form of phenylalanine found in proteins throughout the body; (2) D-phenylalanine, a mirror image of L-phenylalanine that is synthesized in a laboratory; and (3) DL-phenylalanine, a combination of the previous two forms.The body converts phenylalanine into tyrosine, another amino acid essential for making proteins, certain brain chemicals, and thyroid hormones. Symptoms of phenylalanine deficiency include confusion, lack of energy, decreased alertness, decreased memory, and diminished appetite.