[Blarg]

Water intake has been correlated to mood, too. By way of anecdote, I tried myself to see if increasing my water intake seemed to make much difference, and it did. I feel noticeably more energetic when I'm drinking more water than usual. Even when I'm not sprinting to the bathroom.

As to why, I don't know, but water is sometimes called the universal solvent. Your body needs it for most everything it does. It certainly needs it for passing waste out of your body. As well as helping me do all kinds of other things, I'm figuring it helps me get waste out faster when I drink a lot of it. That might have spillover effects into my mood.