Sodium lactate is the sodium salt of lactic acid. It occurs naturally in the skin as part of the skin’s NMF (Natural Moisturizing Factors) and is an excellent humectant. It is a significantly stronger humectant than vegetable glycerin, with over twice the water-holding capability.
In skincare products, it is used primarily as a humectant. It is second only to hyaluronic acid in its ability to hold water It can also reduce tackiness in formulas, and is keratolytic. Sodium lactate increases skin hydration in both leave-on and rinse-off applications.