Why does the skin on my fingers get all “pruney” in the bathtub?

You've undoubtedly observed your fingers pruning if you've ever had a lengthy bath or spent time in a pool. The tips of your fingers, and sometimes the entire finger, acquire wrinkles and creases similar to those on a prune. Pruning is normally innocuous and disappears on its own. However, prolonged trimming or pruning that does not occur as a result of water might be a sign of an underlying medical problem.

Pruning was formerly thought to be caused by your fingers soaking water, according to the medical establishment. Pruny fingers are now understood to be caused by blood vessels that constrict underneath the skin's surface. The condition is linked to nervous system function. Water can have this impact, but there are other factors to consider. For example, the pruning might be caused by fluid or nerve injury, both of which can indicate an underlying medical problem.

This occurs because the top layer of skin on fingers and toes (called the stratum corneum) is more porous than the layers of skin underneath, making it better at absorbing water. However, instead of expanding, our fingers and toes shrivel due to the way the layers of skin are connected: the top, swelling layer of skin is attached underneath to tissue that does not swell, thus the skin bends to fit the greater surface area. As a result, your fingertips have the appearance of prunes. Alternatively, raisins. The water from your skin evaporates into the air as you dry, and your skin rapidly returns to normal.