On the flip side, acids penetrate deeper into the skin and accelerate turnover for all your skin cells, not just the dead skin sitting up top: “Acids physically turn over the skin cells (which can cause the actual shedding of the skin), which allows new skin cells to generate,” says celebrity esthetician Lisa Guidi, owner of Erase Spa. While also found in natural, plant-based products (lemon, apple cider vinegar, and the like), acids lend a bit more intense exfoliation than the average fruit enzyme. “Imagine that there is glue between skin cells, keeping them together,” explains double-board certified surgeon Melynda Barnes, M.D., clinical director for Rory—an online health care service that creates customizable skin care formulas. “Enzymes break down that glue (the keratin protein), which allows the dead skin cells to be removed or exfoliated from the skin.” Acids, on the other hand, “work by triggering cell death in older skin cells and promoting new skin cells to grow. This results in older cells sloughing off and newer skin cells taking their place.” That’s not to say only sensitive-skinned folk can benefit from enzymes; in fact, Barnes notes that enzymes and acids are frequently used together in products for a dual-approach exfoliation. Similarly, Guidi mentions enzymes work for most skin types, especially acne-prone, oily, and combination skin. That said, you may have to play around with specific acids to find one that suits your skin care needs. Regardless, Guidi mentions specific concerns like hyperpigmentation, sun damage, and active acne can benefit from that forced cell turnover; however, the process can be irritating for those with super-sensitive skin. If acids are too stripping for your taste, enzymes might be more your style.
