While a multiple-step skin-care routine isn’t for everyone, cold, bitter air calls for reinforcements. Meet hyaluronic acid, the magical ingredient that plumps skin’s surface in seconds and makes every other cream work that much harder. The substance attracts water, literally filling in lines and wrinkles. “I call it the Cinderella effect,” says New York City–based Dermatologist Gervaise Gerstner, M.D, referring to the product’s ability to make tired, red, or uneven skin look better in seconds. And the best part is that you can use it under, over, or in between layers of makeup, anytime you need a little extra hydration.

“Because skin already produces hyaluronic acid,” Gerstner says, “increasing [levels] will help the overall hydration of the skin.” She notes that the ingredient has no side effects, does not cause acne, and can be used alone or in conjunction with other anti-aging or preventative products. Although the acid temporarily improves skin’s appearance, it also, over time, “restores the barrier function, giving it the ability to repair and restore faster,” she adds. Winter is coming—why wait?