A new study released on Wednesday suggests that there are few health benefits to drinking large amounts of water.
Drs. Dan Negoianu and Stanley Goldfarb of the University of Pennsylvania assessed published clinical studies on the benefits of drinking water.
They found that while athletes need more water -- along with people who live in hot, dry climates and those with certain diseases -- the average healthy person does not.
In fact, the researchers found no evidence to support the common belief that drinking eight glasses of water a day can result in health benefits, which have long been believed to range from improved kidney function to a more luminous skin tone.
"It's required for life, and I guess that's led people to think, 'well, if a normal amount is good, then extra might be better,'" Goldfarb told ABC News.
"It won't harm you, but you should understand that there's very little, if any, scientific evidence that it's going to benefit you."
Some studies did show that an increased water intake does help the kidney remove substances, such as sodium. However, this did not lead to a health benefit.
Researchers cound not find conclusive evidence for other theories involving greater water intake, including that it helps fight weight gain by keeping a person feeling full, and it improves skin tone.
A study that found that participants who drank more water experienced fewer headaches was found to be too small to be significant.
One interesting conclusion was that how fast a person drinks water seems to determine if the body excretes it or retains it. If water is gulped, it will most likely be excreted. If it is sipped slowly, the body will hang on to it. However, the speed of water intake did not indicate any health benefit.
The researchers point out that although the studies they reviewed did not prove that there is a clinical benefit of drinking more water, there is also no proof that there isn't one.
"Drink when you're thirsty," said Goldfarb. "That's the way your body is designed."
The study entitled "Just Add Water" will be published in the June issue of the Journal of the American Society of Nephrology.
