How Glycolic Acid Works on Skin

Glycolic acid acts as a keratolytic by lowering skin pH at the surface and weakening the desmosomal bonds between corneocytes. The depth and speed of action depend on three variables:\n\n1. Concentration — total acid in the formula\n2. pH — lower pH = more free acid available\n3. Free-acid value — the actual exfoliating fraction\n\n## pH matters more than %\nA 10% glycolic toner at pH 3.5 can be more active than a 15% formula at pH 4.5.