What Is Sodium PCA? Sodium PCA is a naturally occurring hydrating ingredient. Sodium PCA is a humectant that works as a hydrating agent and a skin-replenishing ingredient in a variety of skin and hair care products. Humectants are ingredients that help the skin to retain and preserve moisture. Humectants work by attracting water to the … Continue reading Sodium PCA: Does It Rival Hyaluronic Acid?