Encyclopedia · humectant
Sodium PCA
A salt of an amino-acid derivative found in skin's natural moisturising factor, used as a humectant; no hair study was found.
Cosmetic ingredient
Cost $
What it is
A derivative of glutamic acid that is present in the outer layer of skin. It is a cosmetic ingredient, and the Cosmetic Ingredient Review panel published a safety assessment of PCA and its salts in 2019.
How it works
It binds water in skin. We located no hair-specific mechanism data.
What the studies show
- No hair-specific study was located.
Side effects and safety
It is generally considered a low-risk cosmetic ingredient.
Bottom line
A harmless humectant with no demonstrated hair benefit. We are very unsure it does anything for hair. See humectants and humidity.
Studies 0
No studies are listed for this page yet.
Related
- GlycerinA cheap water-binding ingredient in nearly every conditioner; no peer-reviewed hair study tests it, and the popular humidity rules are untested.
- Amino acidsFree amino acids in conditioners are small enough to enter hair, but there is little evidence that they strengthen it.
- Humectants and humidityHair swells and softens with humidity, but the popular rules about glycerin and humidity have not been tested; panthenol is the humectant with the best fibre data.