By ingredient · Sub-chapter 03
Glycerin, hyaluronic acid, panthenol, aloe — the ingredients that pull water into the hair shaft and keep it there. When they work, when they backfire, and how to use them.
76 how-to's · Updated 30 April 2026 · Avg. 4 min per piece · Edited by Nelly · Beauty & Style Director
Editor's note
Humectants do one thing: attract water. They draw moisture from the air around them — and, if conditions are wrong, from the hair shaft itself. Which direction the water moves depends on the relative humidity of your environment. In low humidity, glycerin-heavy leave-ins will draw moisture out of dry hair and into the dry air, making the hair frizzier and drier than before. In high humidity, they can over-hydrate porous hair and cause hygral fatigue. The ingredient isn't at fault. The context is.
What humectants actually do
Humectants are hygroscopic compounds that attract and bind water molecules. In hair care they are used in conditioners, leave-ins, and styling products to draw environmental moisture into the hair shaft and hold it there. The most common in hair care: glycerin, hyaluronic acid, panthenol (provitamin B5), aloe vera, honey, and sorbitol.
Other ingredients sub-chapters
Everything we've published on humectants
- Glycerin in hair care: the full picture
- Humectants in low humidity — why your leave-in isn't working
- Panthenol for hair: what provitamin B5 actually does
- Aloe vera vs hyaluronic acid in hair
- Hygral fatigue: the over-moisturised hair problem
- Layering humectants and sealants: the LOC method