Lactic acid is an alpha hydroxy acid (AHA). it helps slough away dead skin cells on the surface to reveal improved skin texture and appearance. In some formulas it’s used to balance acidity to an optimal pH. It’s produced by the fermentation of a cultured bacteria via biotechnology. Being a natural moisturising factor (NMF), lactic acid also supports function of the skin barrier and increases skin hydration. It’s a great aha option for most sensitive skin.
About NMF: Our skin naturally produces a chemical barrier to environmental threats and moisture loss called the NMF. Our outer skin layer is around 20-30% NMF, which is a mix of powerful humectants. about 12% of those humectants is lactate (i.e. lactic acid + sodium lactate).