#Skin Anatomy & Biology

The 24-hour skin clock: when collagen synthesis peaks and when TEWL spikes

TL;DR: The skin runs on a 24-hour clock. Cell proliferation peaks at midnight to 4am. Sebum output peaks at noon. TEWL spikes…

The basal layer is where every brightening claim lives or dies

TL;DR: Every brightening serum has to reach a layer about 60 microns deep where melanocytes sit and where pigment gets manufactured. Most…