WHAT ARE CERAMIDES?
The outermost layer of the epidermis is the stratum corneum. CERAMIDES are the major lipid component (along with cholesterol, free fatty acids, and other minor components) of the intercellular spaces of stratum corneum that form the epidermal permeability barrier of the skin. There are multiple classes and species of ceramides. Ceramides can be obtained from plants such as oat, wheat and rice and are then referred to as phytoceramides.
HOW DO CERAMIDES WORK?
The epidermal barrier function which primarily resides in the stratum corneum consists of vertical stacks of anucleate corneocytes (cells on the surface of the skin) packed with keratin filaments embedded in a matrix of filaggrin breakdown products, ceramides, cholesterol, and fatty acids. The stratum corneum provides the first line of defense against the environment including pathogens and allergens. Stratum corneum lipids play a major role in the permeation function of the skin barrier. Ceramides soften the stratum corneum, reduce trans epidermal water loss, and attract water to the stratum corneum.
“WHY” ARE THEY IMPORTANT FOR YOU?
Several skin diseases such as psoriasis and atopic dermatitis are associated with the depletion or disruption of the stratum corneum lipids. Decreased levels of ceramides in the skin influence the barrier function of the skin due to increase in trans epidermal water loss leading to dry skin and eczema.
Evidence has shown that a cream containing ceramides is more effective at reducing water loss through the skin than a traditional moisturizer.