globalmerchant, a person who weighs 75 kg would weigh roughly 166 pounds. Divide that by 2 and you get a consumption of 83 ounces of water. That's 2.5 liters a day, not 5 liters. Plus, a lot of the water one would need a day comes from fruits and other foods anyway.

You are right, no one should be dehydrated, but 5 liters, c'mon! Remember that most people do not weigh 110kg.