Since our skin produces a natural coating of fat, it’s often enough to achieve this effect by using soap and water. Some of the fat layer remains, aiding its replenishment after washing. But too-frequent hand washing makes no sense — and the same is true of too-frequent showering. If the protective fat layer is rinsed away too often, our unprotected skin is exposed to the environment. This gives odour-producing bacteria a better foothold, making us smell more pungently than before: a vicious circle.