A sunburn is a radiation burn. When UVB rays penetrate epidermal structures, they collide directly with the DNA inside keratinocytes, the primary cells forming the outermost layer of your skin. If the repair machinery within these cells cannot fix the genetic damage, tumor-suppressor genes like p53 step in. They command the cells to self-destruct.
This coordinated cell suicide prevents rogue, damaged DNA from replicating. Within 48 to 72 hours after intense exposure, millions of dead skin cells detach from the basal layer simultaneously. The tissue dries out, turns brittle, and lifts from the surface. While the sight of large sheets of shedding skin can be alarming, it proves that your cellular repair defenses worked properly under acute stress.
