There are different kinds of Alpha Hydroxy Acids. Glycolic Acid is the most active and beneficial of the AHA's in skin care. It is a natural ingredient derived from sugar cane. It has the exceptional quality of being able to penetrate the upper layer of the skin, helping peel away the dead skin cells and reinvestigation on the growth of the new skin cells. Glycolic Acid is found to be the most effective acid to be used for peeling since its molecules are the smallest among all acids, allowing superior penetration into the skin. Once inside the cell, it will trigger new formation of collagen and plump up the cell and certain substances in the skin to reduce wrinkles on the skin surface. Glycolic Acid also causes much of the stratum Corneum (the horny outer layer of the epidermis, consisting mainly of dead or peeling cells) to lift off and separate from the underlying skin. This gives the skin a much smoother look and feel. Glycolic Acid has shown to be very effective in the treatment of acne as well.