Our bodies perspire to make us feel cooler.
As long as we can sweat and the sweat can evaporate, we can continue to cool ourselves efficiently. In fact, evaporation of sweat accounts for 90 per cent of our cooling ability.
If we stop sweating or the sweat cannot evaporate, our cooling mechanism will fail. When we become dehydrated, we may stop sweating. On hot, very humid days, our sweat cannot evaporate and our cooling mechanism is extremely inefficient. Take care not to overheat.