Cranky? Drink Water

Even mild dehydration can alter a person's mood, energy
level, and ability to think clearly, according to research from
the University of Connecticut's Human Performance Laboratory.
Tests showed that it didn't matter if the person had just walked
for 40 minutes on a treadmill or had been sitting at rest: The adverse
effects from mild dehydration were the same. These effects can
include headache, fatigue, tension, and difficulty concentrating.
Experts recommend drinking about two quarts of water per day.
-Natural Choices Magazine