Ingredient Encyclopedia

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Ingredient Encyclopedia

Lactobionic Acid (PHA) – Benefits, Side Effects & Uses

by ThankMeNow Editors on Sep 10, 2025
Lactobionic Acid (1$C_{12}H_{22}O_{12}$) is a third-generation Polyhydroxy Acid (PHA) formed by the oxidation of lactose.2 It is a complex organic acid that differs significantly from traditional AHAs due to its larger molecular weight (approx. 358 g/mol vs. Glycolic Acid's 76 g/mol).3 This size prevents the molecule from rushing into the skin, instead allowing it to exfoliate the surface gently and evenly.4 Beyond resurfacing, Lactobionic Acid is a powerful polyhydroxy bionic acid with eight hydroxyl groups, making it an exceptional humectant that can bind huge amounts of water.5 It also functions as a metal chelator, neutralizing oxidation triggered by iron in the skin, which helps preserve the collagen matrix from environmental degradation.6