nutrient
Phenylalanine
An essential aromatic amino acid that supplies tyrosine.
Educational draft · Human scientific and editorial review pending. About review status
Phenylalanine is incorporated into proteins and can be converted to tyrosine, which then enters specialised pathways.
How it works
A precursor for tyrosine
Phenylalanine hydroxylase converts phenylalanine to tyrosine. Tyrosine can then enter catecholamine, thyroid-hormone and melanin pathways.
Related topics
Phenylalanine is used to build Protein
Phenylalanine is one of the amino acids used to assemble proteins.
Evidence: Established · Source checked 2026-09-05 · Sources: NIH National Library of Medicine: Biochemistry, Essential Amino Acids
Worth knowing
It is required from dietary protein. Humans cannot make enough phenylalanine and obtain it from dietary protein.
A closer look
The conversion is enzyme-controlled
The rate at which phenylalanine becomes tyrosine depends on enzyme activity and amino-acid handling.
The conversion has an enzyme step
Phenylalanine hydroxylase converts phenylalanine to tyrosine before tyrosine enters its own specialised pathways.
References
Source-checked local draft.
Human editorial review pending.
Take it into the kitchen
Explore this nutrient in simple meals. Recipe pages show estimated amounts and missing data.
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