The stratum corneum is a skin structure below the surface. It plays a key role in maintaining the water level of the skin below and in regulating the natural moisture flow out from the deeper layers to be lost eventually by evaporation from the skin surface. 

This flow is known as the Transepidermal Water Loss (TEWL). The stratum corneum plays a vital role in controlling and reducing TEWL. With the brick-and-mortar design, the corneocytes in the stratum corneum form a water-retaining barrier embedded in a lipid matrix. 

The lipids and the Natural Moisturizing Factor (NMF) of the stratum corneum are crucial in maintaining the water level of the skin as well as reducing TEWL. The NMF is a collection of water-soluble compounds, such as free amino acids, urea, lactic acid, sugars, peptides, etc., which are only found in this layer. These compounds are responsible for keeping the skin moist and pliable by attracting and holding water. NMF components are hydrophilic and act as humectants attracting and absorbing water. 

Humectants can hold large amounts of water in the skin cells and are also capable of absorbing water from the atmosphere and/or products applied to the skin. The lipids serve to prevent water loss from occurring in the NMF.

If the water content of the stratum corneum falls below 10%, its natural functions are impaired and the skin becomes dry (dehydrated), scaly, and less pliable. These are the changes in the body that can lead to premature aging.

So, you will notice many of our products contain natural humectants such as vegetable glycerin. In addition to humectants our products also include, evening primrose oil, pomegranate seed oil, argan oil - wonderful sources of fatty acids, and almond, avocado, sesame, and olive oils - reduce water loss.