A human being can live without food for more than a month, but no one can stay alive for more than a week without water! All living things need water for their bodies to function. When you take in food, water helps to dissolve it and, along with certain chemicals in your body, it turns this food into energy for you to grow. These chemicals can work only in water.
Also, water is needed to carry the wastes out of your body as well. Since you lose water as you breathe and sweat, you have to have about 21/2 quarts of water a day to stay healthy. This can come from drinking water or other beverages, and from water contained in the food you eat.
About 65% of the human body is water. About 65% of a mouse’s body is water too, while an elephant’s body is 70% water, and an earthworm is 80% water!