Now, this is shocking: the advice we've been getting our whole lives--to drink eight glasses of water a day--may have no medical backing.
"We set out to take a look at the eight-by-eight myth, and we were really unable to find any scientific rationale for it," [University of Pennsylvania kidney specialist Dr. Stanley] Goldfarb told ABC News.
Will water make you feel full so that you'll eat less while dieting? The doctors were only able to find two small studies -- which disagreed.
Neither are there many studies to say that guzzling water will prevent headaches or flush toxins from your body.
"I always laugh when I hear that one," says Stella Volpe, a nutritionist at the University of Pennyslvania School of Nursing. "Your kidneys do that job." Volpe was not involved in today's study, which is published in the Journal of the American Society of Nephrology, an organization of kidney specialists.
So why did these notions take hold? Goldfarb says they found medical-advice sites on the Internet are full of recommendations to drink extra water.
"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," he said.
Which may come as a relief. It's well-documented that bottled water is expensive and environmentally unsound (Seattle has even banned the sale of it), and the AP recently conducted a study that uncovered sex hormones and mood stabilizers--among other unappetizing things--in the drinking water of 41 million Americans.
Are you relieved? Have you actually been drinking eight glasses of water a day? Have you ever tried? It's not easy, right?
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