The old eight-glasses-of-water-a-day myth always seemed suspect. That's a lot of liquid for a day's worth of hydration. And, in fact, numerous specialists have spoken out against the rule. But some authoritative sources, including the Mayo Clinic and NHS Choices, still repeat the guidelines. Today, the debate stops here. A general practitioner in Boston's Medical Journal argues against consuming that many glasses, calling those guidelines "thoroughly debunked nonsense."

She points out that the "legitimate" organizations that perpetuate the myth, like Hydration for Health, have ulterior motives. They recommend 1.5 to 2 liters a day. (8 glasses measures out to 1.89 liters.) Danone, maker of bottled water, among other things, also happens to own the organization. No substantial literature exists to support the claim.

Again, we already knew this. In 2002, a similar study came out of Dartmouth Medical School, where the professor in question argued against the eight-a-day rule.

An American Journal of Psychology article believes the recommendation sprouted when the Food and Nutrition Board of the National Research Council recommended approximately "1 milliliter of water for each calorie of food," which would equals about 64 ounces, or 8 glasses.

But, in the next sentence the council added, that "most of this quantity is contained in prepared foods." People ignored that detail, so the recommendation was misinterpreted.

So no more hyper-hydration. Now that you've got that straight, think of how much you'll save on toilet paper.

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