What it is
Methionine is one of the body's essential amino acids and contains a sulfur group that contributes antioxidant character. In topical formulations it is used as a skin-conditioning agent and can help support a formula's resistance to oxidation. It is typically included at low levels.
Safety & warnings
Methionine is a naturally occurring amino acid generally regarded as well tolerated in topical use, and it is not a recognized fragrance allergen or a comedogenic oil.
Origin & sourcing
Can be produced by fermentation or chemical synthesis; the molecule is identical to the methionine found in proteins.
Questions everyone asks
What does methionine do in skincare?
It works as a skin-conditioning agent and, thanks to its sulfur group, can contribute antioxidant properties to a formula.
Is methionine natural?
It is an essential amino acid found in proteins; the cosmetic ingredient is made by fermentation or synthesis to match that molecule.