We all know about the ‘compulsory’ 8 glasses of water per day, but how true is this? The Mayo Clinic tells us that there is no simple answer to this question, as requirements differ from one person to another. This depends on your lifestyle, among many other factors. In general, the 8 eight-ounce glasses per day holds. One thing you ought to consider is how much you sweat. The more you sweat, the more you should drink. Simply use the 8 glasses a day rule as a base and make the necessary adjustments.