Of all the basic requirements for life, water may be the most underappreciated.
Water regulates body temperature, carries away waste, and delivers nutrients throughout the body.
Blood itself is more than 80 percent water. Each day, through normal activity, the average person loses two and one-half quarts of water due to respiration, perspiration, and elimination, so regular hydration is important. In addition to drinking water, Breitenbach explains that people can receive the equivalent of another two cups of water per day with a regular diet of fruits and vegetables. These beverages act as diuretics and promote water loss through more trips to the bathroom. Physically active people or airline passengers also need to be aware of their extra water needs.