Both salicylic acid and lactic acid are gentle exfoliants that help treat rough patches of skin, albeit in slightly different ways. Salicylic acid is a beta-hydroxy acid that is derived from the bark of certain plants. It works by loosening the “glue” that holds the skin cells on the top layer together. By helping your skin shed dead skin cells faster, newer, healthier-looking skin is revealed, leaving it feeling softer and smoother.

Lactic acid is an alpha-hydroxy acid that’s a natural byproduct of plant and dairy fermentation. It is known to help loosen the bonds that hold dead skin cells together to leave your skin softer, smoother, and with enhanced overall texture.⁵ But lactic acid has another trick up its sleeve. Since it’s part of the skin’s natural moisturizing factor, or NMF, it helps keep your skin hydrated as well.⁶

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3. Diabetes: 12 Warning Signs That Appear on Your Skin: https://www.aad.org/public/diseases/a-z/diabetes-warning-signs
4. Keratosis Pilaris: https://www.mayoclinic.org/diseases-conditions/keratosis-pilaris/symptoms-causes/syc-20351149
5. Baumann, Leslie S. Cosmetic dermatology. McGraw-Hill Professional Publishing, 2009, page 105
6. Baumann, Leslie S. Cosmetic dermatology. McGraw-Hill Professional Publishing, 2009, page 275-276