Ceramides are lipids naturally found in high concentrations in the cells of the upper skin layer, and are essential for the proper function of healthy skin1. There are different types of ceramides which, together with cholesterol and free fatty acids, constitute the lipid matrix in which the upper skin cells are embedded. This lipid matrix is an important barrier for the skin.
The lipid matrix is the only continuous pathway across the upper skin layers2, and is therefore also important for the penetration of topically applied therapeutics. Skin with insufficient levels of ceramides has an increased loss of water across the surface, and thus becomes dry with increased permeability to irritants and allergens3.
In the upper layer of atopic dermatitis skin the levels of ceramides are reduced compared with healthy skin4,5. In a study with both adults and children with atopic dermatitis, a ceramide containing cleanser and moisturiser that was applied twice daily for 6 weeks, showed reduction in disease severity and itching compared with before treatment6.
Furthermore, a laboratory study has shown that some special immune modulators (Th2) displays a characteristic pattern for people living with eczema, leading to reduced ceramide levels in the upper layer of the skin. The authors suggest this to be one of the ways in which the activation of the immune system contributes to the reduced barrier function7.
These findings for people living with psoriasis supports ceramides role as an important component in healthy skin and barrier function, and the effect is very likely of equal importance for people with dry skin.
The concentration of an ingredient is important for its efficacy, and therefore products containing the same ingredient may not necessarily have the same effect as in the studies mentioned above.
Updated: July 2017