Mechanism

Hydration

Stratum corneum water content; central to texture, comfort, and barrier performance.

Review

What it is

Hydration depends on natural moisturizing factor (NMF), intercellular lipids, and applied humectants.

Well-hydrated stratum corneum looks smoother and feels more comfortable, and supports better enzymatic barrier maintenance.

It connects barrier biology, comfort, and visible texture into one axis.

Stratum corneum + lipid matrix that controls water loss and limits irritant entry.

Water diffusing outward through the stratum corneum; rises when the barrier is disrupted.

Ingredient axes

Hydration axis

Water-attracting agents (glycerin, hyaluronic acid, urea) that draw moisture into the stratum corneum.

Hydration axis

A polysaccharide humectant widely used for short-term surface hydration.

Skin barrier axis

Formulations supporting the lipid barrier and reducing transepidermal water loss.