Cosmetic ingredient

PHENYLALANINE

Phenylalanine, shown on ingredient lists as PHENYLALANINE, is an aromatic amino acid, a member of the molecular family that makes up proteins. The L form is incorporated into proteins, and phenylalanine is one of the essential amino acids in the human diet; that helps identify the ingredient, but it does not make it a plant extract or a ready-made protein applied to skin or hair.

INCIPH1 products
CAS number
63-91-2 / 150-30-1
EC number
200-568-1 / 205-756-7
Chemical name
3-Phenyl-L-alanine

PHENYLALANINE: what it is

Phenylalanine, shown on ingredient lists as PHENYLALANINE, is an aromatic amino acid, a member of the molecular family that makes up proteins. The L form is incorporated into proteins, and phenylalanine is one of the essential amino acids in the human diet; that helps identify the ingredient, but it does not make it a plant extract or a ready-made protein applied to skin or hair.

Phenylalanine has L and D forms, with the same basic composition but a different spatial arrangement. The L form is the one associated with proteins; it can be obtained commercially from proteins, whereas an ingredient list does not identify the raw material or manufacturing route used for a particular product.

PHENYLALANINE: what it does in cosmetics

In cosmetics, phenylalanine can take part in skin and hair conditioning. In everyday terms, conditioning means contributing to a surface being kept in good condition, with a more pleasant skin feel or hair that feels softer, more supple and easier to comb when the formula achieves that purpose.

It is also listed for perfuming, meaning a role connected with adjusting a product's scent. That does not mean phenylalanine by itself has a perfume: the L form is described as odourless. Its status as an essential dietary amino acid is about food, not evidence that a cosmetic containing phenylalanine treats pigmentation, skin disease, hair loss or any other condition.

Catalogue presence

Products containing this ingredient

See which products include it and the name used in each composition.