Mất nước qua biểu bì (TEWL)
Sự định nghĩa: The natural movement of water from within the body through the epidermis, where it evaporates from the skin or nail surface.
Why It Matters: High TEWL means more dryness. Products that reduce TEWL help keep skin and nails hydrated.
How Oils Help: By forming a barrier on the surface, oils slow TEWL and reduce moisture loss.
