Eight glasses of water a day myth lead by financial interests, says researcher

Do you carry a bottle of water every place you go? Are you consumed with consuming your eight glasses a day for optimal health? Well, a researcher in Australia says you can give it a rest — you're plenty hydrated already.

In an editorial for the June issue of Australian and New Zealand Journal of Public Health, Dr. Spero Tsindos from La Trobe University says most people get enough water from the foods and beverages — including tea and coffee — they consume regularly and don't need to supplement with copious amounts of water.

He even takes his message a step further by suggesting the eight-glass-a-day rule is a myth invented by plastic water bottle companies who have made it fashionable to tote around what he says have become ubiquitous accessories.

"I would disagree with that," says Tara Miller, a Toronto-based certified nutrition practitioner and owner of The Health Hut. "Even if we were eating a perfect diet, we would need [to drink more water]. While we get water from fruits and vegetables, the type of diet we're eating now — the standard American diet — wouldn't include very many sources of water as it is."

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Miller argues drinking water aids in cellular health, metabolism, muscle and joint function, energy, reduced fatigue and even alleviating headaches and hunger. She explains headaches are often caused by dehydration. And dehydration can easily be confused with hunger, as well.

She suggests that more than eight glasses a day would be beneficial for some very active people and also heavy caffeine drinkers.

"Also if you drink coffee, tea or any other kind of diuretic, you're already losing excess water there, so I would say eight glasses of water a day is good for the average person, and then if you're drinking caffeinated beverages, do two glasses for every caffeinated beverage."

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The Mayo Clinic looks at both sides of the issue in an article titled, Water: How much should you drink every day? And while they agree people do get a lot of water from certain foods and beverages, "these should not be a major portion of your daily total fluid intake. Water is still your best bet because it's calorie-free, inexpensive and readily available."

Their advice? Listen to your body and drink water accordingly. People who are more active, live in warmer climates, are suffering from an illness or who are pregnant or nursing may need to consume more water, because they are losing more fluids from their bodies than others. As long as you're producing 1.5 litres of light yellow urine a day, you're good to go.

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