Sodium PCA

One of the most important parts of the skin's Natural Moisturizing Factor, a mixture of various compounds that keeps the skin’s surface well hydrated. Sodium PCA is used in skincare for its fantastic humectant properties.
Moisturizing
Other functions
Origin
Sodium PCA

Overview

Sodium PCA is one of the most important parts of the skin's Natural Moisturizing Factor, a mixture of various compounds that keeps the skin’s surface well hydrated.

PCA stands for Pyrrolidone Carboxylic Acid and it is derived from an amino acid called glutamic acid. Sodium PCA is a simple sodium salt of this naturally occurring acid. The addition of sodium gives PCA some incredible water-binding abilities.

Sodium PCA is used in skincare products for its fantastic natural humectant properties.

Studies have shown that the levels of PCA are lower in unhealthy skin (i.e. dry, damaged, or diseased). Sodium PCA is able to restore the skin's hydration due to its hygroscopicity (the ability to attract and bind water) and when combined with proline, another amino acid, their humectant effects are enhanced. Sodium PCA is a good ingredient to have in your skincare routine, as it prevents damage to your skin’s Natural Moisturizing Factor.

One research article found that Sodium PCA in a simple water solution does not work and that it has to be incorporated into a suitable vehicle (i.e. an emulsion or cream) in order to perform properly.

Science

1
Oshimura, E., & Sakamoto, K. (2017). Amino Acids, Peptides, and Proteins. Cosmetic Science and Technology, 285–303.
2
Fiume, M. M., et al. (2019). Safety Assessment of PCA (2-Pyrrolidone-5-Carboxylic Acid) and Its Salts as Used in Cosmetics. International journal of toxicology, 38(2_suppl), 5S–11S.
3
Clar, E. J., & Fourtanier, A. (1981). Pyrrolidone carboxylic acid and the skin. International journal of cosmetic science, 3(3), 101–113.