“Humectants are basically ‘water magnets,'” board-certified dermatologist Ava Shamban, M.D., founder of SKINFIVE, told us about the class of ingredients. “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.”
However, when left to their own devices, humectants can actually end up dehydrating the skin. This is because they’re indiscriminate about where they pull in water. For example, when it’s humid, they can pull it from the air around you. But if you’re in an arid environment or spend a lot of time indoors exposed to AC or heaters, then they’ll actually pull it from the deeper layers of the skin, making the skin overall more dehydrated.
This is why humectants should really be paired with occlusives and emollients—either in the same formula or layered together.
For ease, here are some popular humectants to look out for on the ingredient list: