Water is colorless, tasteless and odorless. Because of its numerous and diverse functions in the body, it is often regarded as the most important nutrient. Most people can survive no more than 7 days without water (Williams 2005). Although there is rigorous proof of its benefits, scientists still have trouble objectively advising people how much they need to drink daily to maintain favorable health. This article will plunge in for a look at this mysterious nutrient called H2O.