We are bringing you a new series from Allure: The Science of Beauty, where we answer the tough questions about skincare, hair, and more. If you love beauty and are curious about the science behind it, you're going to love this episode on shampoo. As the old saying goes: An acid a day (or, uh, every few days if you're sensitive) keeps breakouts, fine lines, and dullness away. And no, we don't mean that kind of acid. In this episode, we're talking about AHAs and BHAs — the acids commonly used in skin care to help slough off dead cells and keep complexions bright. First, Michelle and Jenny try a product that proves how powerful acids can be — and completely gross-out their loved ones in the process. Then, dermatologist Laurel Naversen Geraghty (who — fun fact! — is a former Allure editor) stops by to help make sense of when and how to use these powerful skin-care ingredients. If you like what you hear, subscribe to Science of Beauty now on your preferred podcast app: Apple Podcasts: https://podcasts.apple.com/us/podcast/id1531535720 Spotify: https://open.spotify.com/show/7mwxxPykxDZtCQRiqsdK0X Stitcher: https://www.stitcher.com/podcast/allure-the-science-of-beauty Or wherever you get your podcasts.