Water, water, everywhere and you don't have to drink it all.

Water, and lots of it, has been a prescription for health for a couple of centuries now. Interestingly, this article, Junkfood Science: Wellness water — the 8x8 myth, reports that there is very little scientific evidence to support the claim that water consumption brings good health, weight loss, or world peace. In particular, the 8x8, eight eight-ounce glasses of water, regimen is supported by  anecdotes - healthy people drink water. There were no finding to support the claim that these healthy people became healthy because of their water consumption. Again, there's a problem between correlation and causation.

The general guidance - eat a balanced diet and drink fluids when you're thirsty - still holds.