Lactic and Glycolic peels are similar in their actions but the molecules are slightly different. A good rule of thumb is the pure Lactic is best for treating age/sun spots and the pure Glycolic is best for fine lines. The combination is great if you are looking for a revitalizing improvement in tone and texture.
Glycolic Acid is the most active and beneficial of the Alpha-Hydroxy-Acids in skin care and is made from sugar cane. It is the only AHA which is able to penetrate through the cell walls by virtue of its small molecular size. Once inside the cell it will trigger new formation of collagen and plump up the cell to reduce wrinkles on the skins surface.
Lactic acid pulls moisture from the air and holds it on the skin and is less irritating. It is more natural
Salicylic acid is mild and works to encourage sloughing of dead skin cells. It's a safe effective treatment for mild acne, oily skin, textural changes and hyperpigmentation.