Asked by: Paul Waygood, Somerset
Most of the value of handwashing is the physical rubbing and rinsing action that dislodges bacteria from the skin’s surface. A study at Rutgers University in the US found that hot water was no better than cold at removing E. coli. In fact, water that is uncomfortably hot actually increases the bacterial load, because it damages the natural protective barrier of your skin.
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Authors
Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
