It's fat-free, cholesterol free, low in sodium and has absolutely no calories. Water is a fundamental part of our lives. Did you know that 55 - 75% of your body is water and water accounts for two thirds of your body weight? Did you know that you could live without food for about two months but could only survive without water for a few days? Every process in the body occurs in a water based medium. We need plenty of fresh water to stay healthy. Although water covers 70% of the Earth's surface, only 1% of the Earth's water can be used as a drinking source and many of these are polluted or contaminated.