Whats a humectant?
A humectant is a water binding substance that is capable of retaining large amounts of water (relative to their weight) in the skin, thereby helping to keep the skin smooth and supple. Binding of water at the skin surface is accomplished by humectants e.g. glycerin, glycols. Urea is a soluble humectant known as a natural moisturising factor NMF (along with certain amino acids).