Phenylalanine is an essential amino acid used by the human body for cellular activity. The body uses it by converting it to tyrosine, another amino acid, using a gene enzyme called phenylalanine hydroxylase. An enzyme can be thought of as a biological catalyst that helps a chemical reaction but is not destroyed in the process.
Phenylalanine serves in the body as a precursor to the catecholamine family of hormones. The catecholamines include adrenaline and noradrenaline, which are activating substance in the central and peripheral nervous systems as well being produced by the adrenal medulla (adrenal gland). The human body manufactures CoQ10 from amino acids tyrosine and phenylalanine
Tyrosine is used to create various hormones, to produce energy in the body, and to create the skin pigment melanin. The chemical process that creates tyrosine involves the hydroxylation, or addition of an oxygen-hydrogen group, to part of the phenylalanine molecule. This process takes place in the liver and involves the interaction of iron and other enzymes in a complex reaction.
Phenylalanine is also used to produce a number of neurotransmitters such as dopamine. Neurotransmitters are chemicals the brain and nerves use to communicate.
Deficiency of phenylalanine
The body can normally regulate the excess through the phenylalanine hydroxylase reaction, with some exceptions. Some people have a lack of phenylalanine hydroxylase or abnormalities that can prevent the normal processing of the amino acid. People having a phenylalanine hydroxylase deficiency can experience severe mental retardation if the disease is not recognized early.
People with the deficiency will often have a musty odour, particularly in their urine. They may also have pale skin, because the body is not producing tyrosine needed for melanin. Epilepsy and other nerve diseases can also occur from the disease due to the lack of key hormones needed for nerve functions.
Children with non-diagnosed phenylalanine hydroxylase disease will test lower on intelligence tests than healthy children. If it remains untreated, severe mental problems and other medical conditions will occur over time. A strict diet avoiding artificial sweeteners and using low protein intake can prevent the developmental issues from the phenylalanine hydroxylase condition.
Highest sources of phenylalanine in milligrams per 100 grams
- Chlorella (dried) and spirulina (dried) 2777 mg
- Whelks 1648 mg
- Pumpkin and squash seeds 1642 mg
- Peanuts 1427 mg
- Lamb’s liver 1385 mg
- Cheddar cheese 1311 mg
- Almonds 1185 mg
- Sunflower seeds 1169 mg
- Black beans 1168 mg
- Calf’s liver 1140 mg
- Caviar (fish roe) 1092 mg
- Beef (lean mince) 1028 mg
- Almonds 1120 mg
- Tuna fish (tinned) 996 mg
- Quail 980 mg
- Flaxseeds 957 mg
- Pheasant 951 mg
- Sesame seeds 940 mg
- Turkey 935 mg
- Mackerel (tinned) 905 mg
- Cod 896 mg
- Shrimp/prawns 883 mg
- Lobster 866 mg
- Salmon (farmed) 863 mg
- Mussels 853 mg
- Venison 818 mg
- Crab 773 mg
- Walnuts 711 mg
- Eggs 681 mg
- Rye 674 mg
- Chicken 665 mg
- Wheat 656 mg
- Brazil nuts 630 mg
- Quinoa 593 mg
- Soya beans 559 mg
- Squid 558 mg
- Pine nuts 524 mg
- Brown rice 410 mg
For daily requirements of phenylalanine See>> Protein
Excess phenylalanine will appear in the urine, a condition called phenylketonuria.
Related subjects
- A-Z of nutrients
- Brain and mental health disorders
- Epilepsy
- Gland disorders
- Hormones functions and health
- Nerve disorders
- Parkinson’s disease
Join our mailing list to receive your monthly emailed newsletter with all the latest scientific findings for natural health remedies.