Hyaluronic acid. Although somewhat difficult to say (and even harder to spell), the skin-care ingredient commonly found in your favorite serums, sheet masks, and moisturizers, is an important addition to your daily skin-care regimen. That’s because HA, a molecule that occurs naturally in the skin, binds to water to plump up your skin and give it that dewy, glowy effect. 

And it’s clear the word has gotten out about its benefits because Allure‘s Readers’ Choice Awards survey shows it’s one of the most-demand ingredients of skin-care products. But hyaluronic acid does so much more than boost skin’s moisture levels, which is why we asked skin-care experts to better explain the benefits of the ingredient.