What causes skin to wrinkle after being in water for a long time?

Question

What causes skin to wrinkle after being in water for a long time?

Answer 1

The Skin

There are various theories of why fingers and toes wrinkle in water. Most biologists suggest that the tough outer layer of skin made up of dead keratin cells is responsible. Keratin is a protein found in hair, nails, and the outermost layer of our skin.

While a person is in the pool or a bathtub for a long time, the dead keratin cells absorb water. This absorption causes the surface area of the skin to swell, but the outer layer is tightly attached to the living tissue. To compensate for the increased surface area, our skin wrinkles.

Why does this happen to hands and feet and not to other parts of the body? Because the hands and feet have the thickest layer of dead keratin cells. Our hands and feet are subjected to a lot of wear and tear.