The question is simple; the answers have not been and continue to be controversial. The Institute of Medicine reported that an adequate intake for the average man in a temperate climate is about three liters or thirteen glasses of total beverages a day; and two point two liters or about nine glasses for the average women. Mayo clinic writers were correct when they pointed out that studies have produced varying recommendations over the years. Your water needs depend on many factors, including your health, how active you are, whether you are using a lot of muscle activity in sports or work, the temperature and humidity, and where you live. Water is your most important nutrient, making up about sixty percent of your overall body weight and about three-fourths of your brain. Every body organ and tissue and system needs water. Current recommendations suggest keeping it simple. Unless your doctor has restricted your intake for some medical reason, drink enough water to have at least one pale urine a day.