Question: how aha and bha work?
Answer: AHAs (alpha hydroxy acids, e.g. glycolic and lactic acids) and BHA (beta hydroxy/salicylic acid) both act to “unglue” the bonds holding dull, dead skin on the surface. Once those bonds are broken—gently and evenly—skin naturally sheds its spent cells. ... improve the look of dull, uneven skin tone.