Coconut water, which comes from fruit too young to have milk, is low in calories and has less sugar than most juices. In addition, it is also an excellent rehydrater. It contains five electrolytes found in human blood -- Gatorade has only two.
Hangovers are essentially the result of your being really dehydrated. Alcohol is a diuretic, flushing the water out of your body.
Time Magazine reports:
“Long a dietary staple in the tropics, coconut water has recently caught on among athletes, health nuts and bleary-eyed urbanites in the U.S., where sales topped $50 million last year.”