This article cites very little evidence: a link to a single article which itself cites no published research results.<p>And this article on Snopes.com says that there's no compelling evidence for the claim that people require even eight cups of water a day:<p><a href="http://www.snopes.com/medical/myths/8glasses.asp" rel="nofollow">http://www.snopes.com/medical/myths/8glasses.asp</a><p>Also, if you're pissing constantly, wouldn't that be evidence that you're trying to over-hydrate yourself? If you were actually dehydrated, wouldn't your body absorb the additional water you drank rather than excreting it?
Interesting. 3l is about 12 cups.<p>I remember back in the 80's and 90's Dr. Dean Edell on his talk show routinely tried to bash this "8 cups of water a day" rule of thumb as an urban legend.<p>He says in this 2002 post that your body weight * 0.08 is the approximate number of cups of water you should get, but I think that includes all that you normally get from food too.