But here’s the thing about glycolic acid: It has the smallest molecular weight of all the alpha-hydroxy acids, which means it can penetrate the outer layer quite easily (unlike its AHA counterpart, lactic acid, which is larger in molecular size). Meaning, it does its work rather quickly—leading to fresh, rejuvenated skin that’s soft to the touch. Other popular products are those premedicated pads (the beloved gly-pad, if you’ve heard your derm toss the term around), known for removing sweat and residual makeup if a full-on cleanse feels like too much—after a workout, perhaps. In terms of procedures, that’s where peels come into play: A glycolic acid peel is one of the most common AHA peels used in dermatologists’ offices. That said, it’s not a venture you should take on in the comfort of your own home: “In a clinical setting, doctors generally use a glycolic acid peel that is 40 to 50% glycolic acid,” says King, whereas an at-home product will likely have a 10 to 20% solution. That’s because trained professionals can take one look at your skin and know whether it could benefit from that heavier exfoliation or whether you should stick to a clarifying cleanser and call it a day. That said, it’s best to take it slow with glycolic acid (and all exfoliating products, for that matter) until you know just how your skin is going to react. As always: Do a patch test before applying new products to the face. Those with oily skin prone to acne and clogged pores might also fare better with a BHA (like salicylic acid) over this AHA. Again, both are great gentle exfoliants, but if you’re looking for a product to penetrate clogged pores (say, if you suffer from deep, cystic pimples), oil-soluble BHAs might be a better fit for those skin care woes.
