The main purpose of moisterizering is to keep the skin moist. Many conventional creams and lotions form a suffocating film on the skin to prevent moisture loss.

Collagen, elastin and keratin enjoy some popularity as humectants. While they are compatible with the skin and deposit a protective film, they are animal derivatives. Environmental factors (sun, wind, pollution) and the detergents and solvents found in most skin cleansers, actually strip the natural lipid content from the top layer of skin. Topically applied plant phospholipids restore the barrier function of the skin, protecting it from substances such as bacteria and harmful chemicals.