The Barrier Breakdown: Transepidermal Water Loss (TEWL)
Hydration isn’t about adding water; it’s about locking it in.
The skin barrier functions via a classic “brick and mortar” layout: corneocyte cells form the bricks, while an equimolar matrix of ceramides, cholesterol, and free fatty acids forms the lipid mortar. When this lipid bilayer is stripped by harsh alkaline cleansers or excessive exfoliation, Transepidermal Water Loss (TEWL) spikes exponentially. Without sufficient surface lipids to prevent evaporation, the skin dehydrates from the inside out, triggering compensatory oil production, micro-inflammation, and hyper-reactivity.
True skin resilience requires reinforcing the intercellular lipid matrix, not merely applying topical humectants.
What is your go-to ingredient or strategy when you need to reset and repair an over-exfoliated skin barrier?
MBH/PS