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The junky science justifying a hydration habit

 •  • by Paul Ingraham
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Last year I stumbled across evidence that surprisingly mild dehydration can make you a bit pissy and foggy… which turned out to be funded in part by a giant corporation that sells bottled water! Pretty fishy, right? Conflicts of interest aren’t always deal-breakers, but that one is highly suspicious.

And that’s just the tip of an iceberg. There’s much more to read about water and dubious industry-funded science. From “Everything You Know About Cramps Is Wrong, And Gatorade Is Full Of Shit”:

… much of the science surrounding exercise and hydration has been underwritten by Gatorade, which obviously has an interest in pushing the notion of dehydration as a performance killer and hydration as the silver bullet. (In their book The Runner’s Body, Tucker and co-author Jonathan Douglas mention one fear-mongering study that suggests that “dehydration of 2 percent causes performance to decline by up to 20 percent.”)

The whole thing is terribly damning and makes you wonder if any good science about hydration has ever actually been done. I especially liked this bit about cramps:

So “your muscles get tired and stop working correctly” doesn’t seem like it should be some mindblowing new theory. But it’s only relatively recently that we’ve taken it seriously as an explanation for cramping.

As opposed to being low on blood levels of Gatorade. Read it all: it’s quite good, albeit depressing. Or just read the title of this letter to a journal, which pretty much sums it up:

“Time for the American College of Sports Medicine to acknowledge that humans, like all other earthly creatures, do not need to be told how much to drink during exercise”

And speaking of how much water is too much water

Here’s the most entertaining read on the how much topic: What Happens To Your Body When You Drink Too Much Water?

Assuming rat biology and human biology are interchangeable when it comes to the quick consumption of large volumes of water, if 100 people each weighing 150 pounds each drank about six liters of water all in one go, around fifty of those people would die, and the cause of death would probably be water intoxication.

It is, thankfully, quite difficult to flummox a healthy pair of kidneys accidentally. It is a testament to the water-processing abilities of this organ that most cases of water poisoning are restricted to extreme instances of hazing and drinking contests.

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