The skin contains between 60% to 80% water depending on age, with the majority located in the dermis: the proteoglycans that make up the dermis bind significant quantities of water molecules. The stratum corneum, the most superficial layer of the skin, contains 13% to 15% water. Skin is said to be dehydrated when this percentage falls below 10%. The stratum corneum becomes rough, brittle, and loses its integrity.
Dehydrated skin is due toa failure in the hydrolipidic barrier, which is no longer able to retain water. Skin dehydration is often linked to environmental factors (cold, wind, pollution, sun, etc...), stress, fatigue, lifestyle (smoking, insufficient hydration, alcohol consumption, use of overly harsh/abrasive cosmetic products) and the use of certain medications (anti-cholesterol, anti-acne, etc...).
All skin types require hydration. However, it is even more urgent to address dehydrated skin. Papyrus native cells limit insensible water loss (IWL), which is the natural evaporation of water through the skin. On the other hand, they promote the creation of lipids (free fatty acids, cholesterol, ceramides, etc...) found in the stratum corneum of the epidermis, the very ones that help maintain cohesion between the corneocytes, the cells of the stratum corneum that act as a skin barrier. Thanks to this improved hydrolipidic balance, the epidermis limits its dryness and ensures better protection against external aggressions.