No real evidence for 8 glasses of water

PHILADELPHIA, April 3 (UPI) -- U.S. adults have long been told drinking eight glasses of water daily is healthy, but University of Pennsylvania researchers say the evidence is thin.

So the advice goes, drinking all that water is helpful for a range of health benefits from keeping organs healthy to warding off weight gain and improving skin tone.

Dr. Dan Negoianu and Dr. Stanley Goldfarb of the University of Pennsylvania in Philadelphia reviewed the published clinical studies on drinking water and found solid evidence that individuals in hot, dry climates, as well as athletes and those with certain diseases have an increased need for water. However, no data exists for average, healthy individuals.

Studies show increased water intake improves kidney function, however, the studies do not indicate any sort of clinical benefit.

Some propose that drinking more water helps fight obesity, but the researchers say studies on water and weight maintenance were inconclusive.

Headaches are often attributed to water deprivation, but there is little data to back this theory. Water has also been touted as a skin elixir, but no studies have shown any clinical benefit to skin tone from increased water intake.

The findings are published in the Journal of the American Society of Nephrology.