Perspiration is a mechanism for keeping the body cool in a hot environment. This is important, because if body temperature rises above the average temperature of by more than a few degrees, it could be life threatening. When the body temperature rises above the normal in hot surroundings, the sweat glands produce sweat which evaporates on the skin. This transfers the heat from blood vessels in the skin to the surrounding air. Sweating may also be triggered by pain, by intense emotions, fear or after eating very spicy food.