As
Aspartic Acid
ASPARTIC ACIDHydrator
An amino acid in skin’s own moisture-holding mix. Older skin had more of it than young skin, yet was drier.
The evidence, graded
emergingAspartic acid is one of the free amino acids in the skin's natural moisturizing factor (NMF). In one study, older people's skin had more of these amino acids, including aspartic acid, and more of the enzyme that releases them, than young skin. Yet it held less water. The authors read the extra as the skin compensating for dryness. The study did not test aspartic acid in a product.Tsurumachi 2023 · J Dermatol Sci ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
L-aspartic acid
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