Theory 43/Biology & physiology/Skin barrier
Barrier Is Lipid Against Water
The claim
Skin water loss is set by the ratio of lipid packing order to hydration, so a well-hydrated stratum corneum loses more water than a dry one.
01Mechanism
Water plasticises the lipid lamellae; the ratio determines permeability.
02Prediction
Loss should track the ratio.
03Refutation
Loss tracking lipid amount would remove packing order.