Focus on Amino Acids: Phenylalanine

You are probably most familiar with phenylalanine from reading the side of Coke bottles on the kitchen table: "Phenylketonurics: This product contains phenylalanine." Phenylalanine is essential to our vital processes. Today we are looking at phenylalanine and its function in the body, and why phenylalanine amino acid supplements are sometimes recommended.

The Basics

Phenylalanine's formal name is (2S)-2-Amino-3-phenylpropanoic acid, and its chemical formula is C9H11NO2, which means it is composed of 9 carbon atoms, 11 hydrogen atoms, one nitrogen and two oxygens. These atoms are common to all amino acids; however, the proportions of them changes. Phenylalanine is an essential amino acid, although the word "essential" means we must get it from our diet. Phenylalanine is one of the amino acid supplements that our body needs. Phenylalanine is quite close in structure to dopamine, epinephrine, and tyrosine -- dopamine and epinephrine being essential neurotransmitters that are used in daily brain function.

Why do we need phenylalanine?

It is essential to so many basic processes in our bodies -- and we can’t manufacture it ourselves. Phenylalanine, whether from food or from amino acid supplements, helps in:

• The production of adrenaline
• The production of catecholamines in the brain -- dopamine, epinephrine and norepinephrine
• It has an analgesic effect -- helping reduce the sensation of pain
• It can act as an appetite suppressant when we are full, by regulating the release of digestive hormones

Food sources of phenylalanine

Phenylalanine is essential to include in your diet, but using concentrated sources (like Coke, or even amino acid supplements) can harm some people. Phenylketonurics have trouble utilizing the phenylalanine that they intake, and an overdose of this amino acid eventually leads to medical and mental problems such as progressive retardation and seizures. These people are better off getting their phenylalanine from natural food sources like:

• Almonds
• Avocadoes
• Pumpkin seeds
• Peanuts
• Eggs
• Cheese
• Corn
• Bananas
• Brown rice