Not having enough water can surely do a number on your body, but can also put you in a crummy mood. Tufts University researchers found that dehydration is related to bad mood, tiredness, and even confusion. So drink water and be merry(er)!
References
Bliss, R.M. (2009). Dehydration Affects Mood, Not Just Motor Skills. USDA Research Service. http://www.ars.usda.gov/is/pr/2009/091123.htm?pf=1.
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