It’s Time to Declare Independence from the Eight-Glasses-of-Water Urban Legend

By Lizzie Buchen | April 3, 2008 11:02 am

We’ve all been subjected to the health admonition of drinking eight, eight-ounce glasses of water per day—known as 8×8. Humans, apparently, have evolved a chronic water deficit, and must constantly replenish their dessicated bodies with high volumes of fluid until their urine runs clear. Water is supposed to be good for your skin, your weight, your purity, and your brain—which is, afterall, 74% water.water.jpg

Balderdash, says a new review of the scientific literature by kidney gurus Dan Negoianu and Stanley Goldfarb from the University of Pennsylvania. They found that for the average, healthy individual, there is no evidence that increased water intake benefits organ functioning, appetite, headaches, skin tone, or substance clearance from the kidneys—and the origin of 8×8 is a mystery. The human body didn’t evolve a chronic thirst—it evolved a great capacity for maintaining proper water balance in the face of variable intake.

These findings support an earlier study by Heinz Valtin from Dartmouth, which found no support for 8×8, and debunked a few other myths. He found that dark urine does not mean dehydration, caffeinated beverages “count” as fluid intake, thirst doesn’t mean “it’s too late,” water doesn’t prevent (or help) constipation, cancer, or heart disease.

However, barring extreme cases (e.g. overcompensating marathon runners and Ecstasy users), excess water is pretty harmless (aside from the possible guilt at not achieving your health goal, polluting the environment with plastic bottles, and possibly swallowing some tranqs).

So what’s the origin of 8×8 evangelism? Valtin cites one speculation. In 1945, The Food and Nutrition Board of the National Research Council wrote that “an ordinary standard for diverse persons is 1 milliliter for each calorie of food,” which would amount to about 2–2.5 liters, or 64–80 ounces per day. But eager readers may have missed the following sentence, which noted that “most of this quantity is contained in prepared foods,” particularly fruits and vegetables, but even in meat, bread, and nuts. And thus was born our obsession with water.

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  • Susanna Gross

    The recommendation for 8 cups of water daily came from the American Dietetic Association, and it was a result of a research paper that I read in April 2001 which used to be posted at The article said the average
    sedentary woman needs 9cups of water a day of which roughly 5cups come from
    foods and digestion. Men need 12cups, which means they need to drink roughly
    7cups a day. It was distorted in the “urban myth” version, but not that much. The
    biggest problem was the urban myth ignores gender and size and discounts water
    from digestion and other beverages.

  • Brad Hamilton

    My wife told me about this article and I had to write in because this doctor is a farce. Dr. Stanley Goldfarb of the University of Pennsylvania says, “If you want to throw away your water bottle, feel free to do so.” There is a lot of scientific evidence.

    I wouldn’t believe anything he says. Please go to and read about this. Every disease that is known to man has been help by water. Our bodies are 80% water and when our body does not have enough water the first signs of dehydration are acid reflux and constipation. Over time dehydration, acidosis and free radicals cause disease.

    Sounds like he gave up being a doctor that truly helped people to get well and stay well.

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