“Humectants are basically ‘water magnets,'” board-certified dermatologist Ava Shamban, M.D., founder of SKINFIVE, says about the ingredient category. “They work to help pull moisture from the air into the upper layer of your skin to keep the skin cells hydrated, plump with a firmness and bounce.”
If you’re looking for an instant (albeit temporary) plumping effect, pat a humectant serum on damp skin before sealing everything in with moisturizer. Your skin will look bouncier almost immediately. “Think of the skin as an actual sponge,” adds Shamban. “When it is dry, it is thin, brittle, not pliable, rough in texture, dull, and sallow in color. Run it underwater, and it is instantly plump, dense, and smooth. Even the color is brighter.” The humectants are what help usher that water into the “pores” of the sponge and hold it there, making the appearance juicy and full of moisture.
Of all the humectants out there, glycerin and hyaluronic acid tend to be the most beloved. Find our favorite HA serums here.