(LONDON) -- How much water should we drink? It's a debate that seems to never be put to rest in part because doctors and health organizations send conflicting messages.
Many physicians will offer up the eight-glasses-a-day adage, though there is no actual research suggesting why this amount should be a goal. For our skin, for our waistline, for our kidneys -- little snippets of advice seem to be perpetually passed around, all consolidating in a singular chant: drink more water, it's good for you.
But why? This is the question that a group of dissenting medical opinions have been posing over the past few years. In a nutshell, their argument is this: there's no evidence that drinking more water helps our health, so shouldn't we just drink when we're thirsty?
That's the take-home message Dr. Margaret McCartney, a Scottish physician, is putting forth in her opinion piece published in the British Medical Journal Tuesday.
The concept that we must drink six to eight glasses of fluids a day to prevent dehydration is "not only nonsense, but is thoroughly debunked nonsense," she writes.
McCartney is up in arms about the western world's tendency to over promote water in large part because she feels that promotion is guided by the beverage industry, not by medical science.
"We can emphasize non-evidenced based things too much," she told ABC News, which detracts from the real health messages we should be sending about exercise diet, and not smoking.
McCartney also calls out several water myths that are currently promoted by European bottled water producer, Danone: that drinking water will help you lose weight, that kids need to drink more water in order to concentrate in school, and that the lack of those eight glasses a day will lead to health problems.
"There is still no evidence that we need to drink more than we naturally want," she writes.
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