Gem of the Week: Forget 8 Glasses of Water a Day

AlexBClark/<a href="http://www.flickr.com/photos/37072792@N06/4292188381/sizes/z/in/photostream/">Flickr</a>

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For many years, people have been told they should drink eight eight-ounce glasses of water a day. That’s 64 ounces, or nearly 2 liters. This week,  Scottish practitioner Margaret McCartney is calling it “thoroughly debunked nonsense” in the current issue of the British Medical Journal.

McCartney took on medical claims disseminated by Hydration for Health, a water-pushing health organization created by the company that owns Volvic and Evian. McCartney wrote that she did not see any high-quality scientific literature provided by Hydration for Health proving drinking so much water was essential. In fact, she found evidence that mental performance suffers when people drink more water than they’re thirsty for. “In other words, there is still no evidence that we need to drink more than we naturally want, and there may be unintended harms from an enforcement to drink more water,” McCartney wrote.

While McCartney didn’t see evidence backing up the 2-liter-a-day rule, she did see bottled water companies pushing the “water=health” idea to sell more of their products. As McCartney wrote on her blog: “The bottled water industry is pushing the idea that we should drink more than we normally would with the promise of health benefits, and I don’t think there are any. That’s all. And I would recommend tap rather than bottled water: cheaper, and far better for environment.” The bottled water companies were not happy with McCartney’s attitude. In response, the European Federation of Bottled Waters wrote a letter to BMJ about McCartney’s article and cited a recommendation that “at least two liters of water should be consumed per day.”

The British National Health Service still recommends that everyone drink “six to eight glasses” a day, but in the US, the Mayo Clinic’s site says that the eight eight-ounce glasses of water a day “isn’t really supported by scientific evidence” and that “if you drink enough fluid so that you rarely feel thirsty” and produce enough clear or light yellow urine a day, you should be fine.

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SIX TRUTHS

Reclaiming power from those who abuse it often starts with telling the truth. And in "This Is How Authoritarians Get Defeated," MoJo's Monika Bauerlein unpacks six truths to remember during the homestretch of an election where democracy, truth, and decency are on the line.

Truth #1: The chaos is the point.

Truth #2: Team Reality is bigger than it seems.

Truth #3: Facebook owns this.

Truth #4: When we go to work, we're in the fight.

Truth #5: It's about minority rule.

Truth #6: The only thing that can save us is…us.

Please take a moment to see how all these truths add up, because what happens in the weeks and months ahead will reverberate for at least a generation and we better be prepared.

And if you think journalism like Mother Jones'—that calls it like it is, that will never acquiesce to power, that looks where others don't—can help guide us through this historic, high-stakes moment, and you're able to right now, please help us reach our $350,000 goal by October 31 with a donation today. It's all hands on deck for democracy.

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