The whole body is made up of microscopic cells. There are about 100 trillion of them in one adult.
Like all cells, skin cells are always being replaced. Every minute, about 30,000 to 40,000 dead skin cells flake off. They have to make room. The body is always making new ones. In fact, about 28 days from now, your skin will be totally new! When the dead layers pile up and don’t shed, they cause problems. These include calluses, warts, and thick white skin flakes of psoriasis (suh-RI-uh-sis).