Pyrrolidone carboxylic acid (or PCA) is a humectant (attracting and retaining moisture in the skin) derived from amino acids.
PCA is naturally occurring within the skin and plays a role in the skin's natural moisturizing factor (NMF), a group of substances that ensure moisture balance within skin. The most commonly used PCAs in skincare are sodium PCA, calcium PCA, magnesium PCA and potassium PCA, all which are used to boost and maintain hydration and strengthen the skin barrier.
