75% of Americans are chronically dehydrated. It is probable that similar percentages apply to 90% of the world population. In 37% of Americans, the thirst mechanism is so weak that it is often mistaken for hunger. Even mild dehydration will slow down one's metabolism as much as 3%. One glass of water shuts down midnight hunger pangs for almost 100% of the dieters studied in a University of Washington study. Lack of water is the #1 trigger of daytime fatigue.
Research indicates that 8-10 glasses of water a day could significantly ease back and joint pain for up to 80% of sufferers. A mere 2% drop in body water can trigger fuzzy short-term memory, trouble with basic math, and difficulty focusing on the computer screen or on a printed page. Drinking 5 glasses of water daily decreases the risk of colon cancer by 45%. It can slash the risk of breast cancer by 79%, and reduce the risk of developing bladder cancer by 50%.