WHAT IS SKIN HYDRATION?

When we speak about hydration of the skin, we don't mean the skin in its entirety, but the uppermost layer of the epidermis: the stratum corneum or the cornified layer.

The cornified layer is made up of corneocytes, which are flattened epidermal cells that are connected by specific lipids.

This skin layer has remarkable protective and defensive properties against external aggression. Only 10 to 15% of it is water. When its water concentration is lower than 10%, the skin is dehydrated.

Immediately below the cornified layer, there is a hydrolipidic film that covers the surface of the epidermis. This is an emulsion made of water and lipids that is produced by the sebaceous glands. This hydrolipidic film forms a protective coating for the skin. Its hydrophobic composition (lipids) helps the skin maintain its suppleness, improve its protection and regulate the body's water content by preventing transepidermal water loss.

20% of our body's water can be found in the skin. Hydrating the skin is therefore essential since:

• Well hydrated skin is supple and soft,
• well hydrated skin has a radiant tone
• Proper hydration prevents tightness and itching and maintains good skin comfort