Facts and Food Sources of Phenylalanine


Phenylalanine is an amino acid which is a building block of protein. Phenylalanine has three forms L-phenylalanine, D-phenylalanine and the mix made in the laboratory known DL-phenylalanine. L-phenylalanine is an essential amino acid found in proteins. It is a precursor for catecholamines such as dopamine, tyramine, norepinephrine and epinephrine which are neurotransmitters acting as adrenalin like substances. Phenylalanine is categorized as neutral and nonpolar because of inert or hydrophobic nature of benzyl side chain. L-isomer is used to biochemically form proteins which are coded by DNA. It is a precursor for tyrosine, the monoamine neurotransmitters dopamine, epinephrine and norepinephrine and the skin pigment melanin. Its major dietary sources include fish, meat, cheese, eggs and milk.

Phenylalanine is useful for skin problems known as vitiligo, attention deficit hyperactivity disorder (ADHD), depression, multiple sclerosis, Parkinson’s disease, osteoarthritis, acupuncture anesthesia, weight loss, and rheumatoid arthritis and alcohol withdrawal symptoms. For vitiligo or dark spots on skin, apply it directly on skin. Naturally it is found in breast milk of mammals and used to manufacture food or drink products. It is a precursor to neuromodulator phenethylamine which is a compound used as a dietary supplement. Phenylalanine is an essential amino acid which is not synthesized de novo in humans or other animals who must consume phenylalanine and phenylalanine containing proteins.

It is highly stuffed in human brain as well as plasma. Phenylalanine’s normal metabolism demands iron, biopterin, vitamin B6, niacin, vitamin C and copper. It is present in high protein foods such as cottage cheese, meat and wheat germ. Artificial sweeteners which contain aspartame are an additional dietary source of Phenylalanine. In sufficient amounts, phenylalanine acts as metabotoxin and neurotoxin.

Dietary sources

Food name Weight (g) Phenylalanine (g)
Turkey 863 9
Soybeans 186 3
Spirulina 112 3
Mungo beans 207 3
Cottonseed kernels 149 3
Winged beans 182 2
Hyacinth beans 210 2
Kidney 184 2
Navy beans 208 2
Yardlong beans 167 2
Chickpeas 200 2
Swiss cheese 132 2
Adzuki beans 197 2
Mothbeans 196 2
Peanuts 146 1
Fontina cheese 132 1
Butternuts 120 1
Monterey cheese 132 1
Provolone cheese 132 1
Almonds 145 1


Health Benefits of Phenylalanine

Let us discover the health benefits of Phenylalanine:

  1. Helps with depression

Phenylalanine promotes euphoria and assist depression patients. Yet the exact mechanism is not known. Supplements of D-Phenylalanine improve depression patients in about 20 days. Phenylalanine improved core symptoms of depression such as agitation, depressed mood and retardation. It also slightly improved sleep disturbance and anxiety. It showed no effect on hypochondriasis and compulsiveness. Some depression patients have low urinary excretion of phenethylamine. It is discovered that high level of phenethylamine showed no improvement so treatment is benefited with low phenethylamine.

  1. Vitiligo treatment

Phenylalaine helps in treating vitiligo, a skin problem where skin loses its color. It is an autoimmune disease where the immune system attacks cells which make pigments in skin. Use of topical and oral L-phenylalanine with medication and UV therapy, it improved vitiligo in more than 75% of patients. This treatment showed no side effects discovering safety and usefulness of L-phenylalanine for treating vitiligo.

  1. Increase dopamine levels

It is a direct precursor of tyrosine in the body. Then it could be converted into dopamine which has a crucial role in various physiological processes such as pain perception and reward system in brain. Adequate dopamine levels could be seen in individuals having Phenylketonuria which is a genetic disorder showing inability of converting phenylalanine to tyrosine resulting in low level of dopamine. It not treated, it causes severe intellectual ability. High phenylalanine could promote catecholamine neurotransmitters such as adrenaline, dopamine and noradrenaline levels. People having deficiency of phenylalanine lowered the level of phenylalanine and reduce synthesis and release of dopamine.

  1. Effective Acupuncture Anesthesia

D-Phenylalanine promotes natural opioids in body by hindering enzyme carboxypeptidase which diminishes enogenous opiods in the body. Patients undergoing tooth extractions when given D-phenylalanine supplements before anesthesia showed effects of acupuncture anesthesia upsurged by 35% in comparison to placebo group. The study shows that deficient in phenylalanine, supplementation of tyrosine lowered the time of reaction in response to stimulus. As tyrosine does not dissolve well in water, the direct supplementation is not found to be efficient which promotes phenylalanine concentration could be a great alternative for producing more dopamine in the body.

  1. Alleviate symptoms of Alcohol Withdrawal

Patients having alcohol detoxification therapies, stress due to withdrawal symptoms could lower natural opioids or dopamine in the body. It could promote opioids and dopamine. Study shows that patients with alcohol withdrawal symptoms when received D-phenylalanine supplements showed reduction in psychiatric symptoms. Treatment that lasted for 40 days shows that D-phenylalanine alleviated stress common to all patients.

  1. Improve ADHD symptoms

Increase in levels of dopamine by supplementation of phenylalanine assist ADHD symptoms. Study shows that supplements of DL-phenylalanine improved symptoms such as restlessness, anger and concentration. The treated group showed improvement in mood due to increased dopamine synthesis. Increment in dosage showed no effect on effectiveness of phenylalanine started waning. ADHD is a disease which varies from one case to other and using phenylalanine with other treatments showed better outcomes.

Phenylalanine Side Effects

  • It may cause hike in blood pressure.
  • Phenylalanine may upsurge anxiety and nightmares.
  • It could interfere with uptake of Parkinson’s drug into brain.
  • Not to be used by people with phenylketonuria.
  • Consult the doctor if side-effects are experienced such as nausea, headache and heartburn.

What happens in deficiency of Phenylalanine?

People with deficiency of Phenylalanine experience the symptoms such as confusion, lack of energy, depression, decreased alertness, memory problems and lack of appetite.

What happens with an over usage of Phenylalanine?

It is not recommended to use more than being prescribed. With an intake of more medication does not improve symptoms but lead to poisoning and serious side effects.









  • User Ratings (0 Votes)

About Author

Comments are closed.