Glycolic acid is most commonly derived from sugarcane and belongs to a group of plant-based acids called alpha-hydroxy acids (AHAs). This resurfacing acid is found in many skin care products works to fight acne, shrink pores, and fade dark spots. Because glycolic acid is a small molecule, it can penetrate deep layers of the dermis to stimulate collagen and hyaluronic acid production, which can help reduce fine lines and wrinkles.