One of the biggest hazards of heat waves is to health. People of all ages can suffer the effects of a heat wave, but the ill, very young, elderly, or overweight tend to be affected more severely. Even though warnings and advisories are given, people often don’t follow the guidelines in areas as basic as drinking a lot of water. When the human body sweats in large amounts, salt and other minerals are lost which have to be replaced. Exercising during a heat wave is never a good idea; but even with regular exertion, it’s advised to replenish the body’s supply of electrolytes.