The Difference Between Glycolic Acid, Hyaluronic Acid & More

Navigating the confusing world of skin-care ingredients can lead us deep into the depths of Google trying to figure out what works, what doesn’t, and why high school chemistry didn’t prepare us for any this. One thing we do remember from lab experiments, though? Acids. When used in skin care, these are the exfoliating ingredients that make skin fresh and glowy, and can treat and even prevent acne, wrinkles, and spots.

“Acids can dissolve skin cells, and when you [use them] in a small dose, [they] will take off the dead skin layer to give you brighter, smoother skin,” explains Manhattan dermatologist Macrene Alexiades, MD, of Dermatology and Laser Surgery Center of New York. “Other acids can also penetrate into the hair follicle to help break up the buildup that causes acne or get between skin cells for anti-aging.”

The trick is finding exactly the right acid and product type — cleanser, mask, serum — for your skin type, as sensitive, acneic, oily, dry, and combination skin all benefit best from different ingredients. Ahead, your guide to which acids will work best for your skin type.