Our skin is made up of layers of dead skin cells that form a barrier around fresh cells, causing a dull complexion and clogged pores. AHAs are different from granular scrubs in that they actually dissolve the protein bond that connects the dead cells to healthy cells. Once the outer layer is removed, a brighter skin tone and improved texture is revealed. For instance, when using a glycolic acid for acne, the acid penetrates the pores and fights the bacteria that cause your breakouts. It also helps with inflammation and reduces the oil below the skin's surface.
In addition, as the AHAs exfoliate the skin, sun spots and blemishes fade, and topical treatments like moisturizers, acne creams and serums are better able to penetrate the skin.