Water is the basis for a large number of body fluids, most common of them being our blood. Saliva is another good example. In fact, more than half of our body is composed of water. Water serves several functions in our body. It is part of catabolism, process in which larger molecules are broken down and also part of anabolism, where smaller molecules combine to form larger molecules. It also carries out its role as the universal solvent by dissolving a number of solutes in it. Water also helps us maintain our body temperature. We continually lose water from our akin, through urine and feces, breathing, etc. And that is why we need a regular intake of water (to make up for the continual loss and to ensure smooth functioning of various body operations).
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