What Are the Benefits of Phenylalanine?

Phenylalanine is an essential amino acid, needed for proper growth and functioning of the central nervous system. It has been used to treat depression and chronic pain as well as other malfunctions of the central nervous system. Humans and animals can't produce their own phenylalanine so they must obtain it from their diet.

Three Types

There are three types of phenylalanine. The first, L-phenylalanine, is the only natural form and is effective for regulating mood, alertness and appetite. L-phenylalanine can be found only in plants and microorganisms. D-phenylalanine is an exact synthesized version of L-phenylalanine and is effective for controlling pain. Finally, DL-phenylalanine is a combination of the two other types and found to be effective for both mental alertness and pain control. Phenylalanine supplements are available in capsule, powder, tablet and topical gel formulas.

Benefits

Phenylalanine is needed by your body to help it make three necessary neurotransmitters: dopamine, norepinephrine and epinephrine. Neurotransmitters are the chemical messengers that send information across the synapses of your brain's nerve cells. Phenylalanine helps by stimulating those nerve pathways that can reduce depression and chronic pain. Conditions that might benefit from phenylalanine are arthritis, speech difficulties, walking disabilities and severe menstrual cramps. It has been used to treat mild Parkinson's disease and schizophrenia. Rehabilitation clinics sometimes use phenylalanine to lessen the symptoms of alcohol withdrawal. Vitiligo is a skin condition where skin loses pigment in patches. Topical phenylalanine combined with UVA radiation can lessen these white patches. It can be used in combination with other amino acids to treat children with ADHD; however, some caution that excess phenylalanine can make the child nervous, jittery and even more hyperactive.

Side Effects and Cautions

Large doses of phenylalanine can cause nerve damage. Do not take phenylalanine supplements if you are already on prescription antidepressants as it can interfere with the drug. Patients with high blood pressure or migraines should not take phenylalanine either. As with any supplement or medication, check with your doctor for proper dosage. PKU syndrome, also known as phenylketonuria, is a metabolic disorder where the body can't break down certain proteins and amino acids due to the lack of a specific enzyme. The body can't remove excess phenylalanine and it can build in the bloodstream. A test is usually done on infants during their stay in the hospital after birth to determine if the infant has PKU syndrome. Patients with PKU syndrome can experience nausea, heartburn, headaches and eventually nerve damage with too much phenylalanine.

Deficiency Symptoms

Symptoms that you might have a deficiency of phenylalanine include lack of appetite, memory loss, inability to focus or concentrate, lethargy and confusion. The deficiency can also result in stunted growth and muscle weakness.

Dietary Sources

The natural form, L-phenylalanine is found in many foods, such as lean proteins including fish, pork, lean beef, poultry and eggs. Dairy products that contain phenylalanine are milk, yogurt and cheese. Tofu, soybeans and soy products are also lean sources of phenylalanine.