Humectant: Definition, Properties and Cosmetic Applications

What Is a Humectant?

A humectant is a substance that has the ability to attract and retain water. In cosmetic formulations, humectants are primarily used to support the water content of the skin or hair and improve the moisturising properties of a product.

Common cosmetic humectants include glycerin, propylene glycol, sorbitol, urea and hyaluronic acid.

How Do Humectants Work?

Humectants interact with water and help maintain moisture within the formulation and, depending on the ingredient and application, within the outer layers of the skin or hair.

Their effectiveness depends on factors such as the concentration used, the formulation, environmental conditions and the combination with other moisturising ingredients.

Humectants in Cosmetic Formulation

Humectants are commonly incorporated into:

• Moisturisers and creams
• Facial serums
• Cleansers
• Body lotions
• Shampoos and conditioners
• Hair treatments
• Masks

They are often combined with emollients and occlusive ingredients. While humectants help attract and retain water, emollients improve skin feel and smoothness, while occlusives help reduce water loss from the skin surface.

Humectant vs. Moisturiser

A humectant is a type of moisturising ingredient, but the terms are not interchangeable. A moisturising product may contain several types of ingredients that work together to improve skin hydration and reduce moisture loss.