The importance of keeping hydrated is constantly being drummed into our minds. Take a glance around your lecture theatre or office and you’re more than likely to see several people toting huge bottles of the stuff in their dedication to getting their eight glasses a day.
It’s not entirely clear where the magic number of eight originated from, but for whatever reason, it’s long been assumed this is the key to good health – vital to maintaining energy and clear skin, amongst a plethora of other benefits.
Before I begin to poke holes in this theory, I should note that water is absolutely essential for all bodily processes, particularly in times of extreme heat or activity. So important is water, that the theme of National Nutrition week last year was ‘Water – Tap Into It’, intended to highlight the importance of hydration and choosing kilojoule-free water over other drinks.
But why eight glasses?
Perhaps the earliest reference to the number can be traced back to the 1970s and respected nutritionist Dr Frederick J. Stare. An “early champion of drinking at least six glasses of water a day,” Stare co-authored a book describing the necessity of certain nutrients for health, where he recommended drinking ‘somewhere around 6 to 8 glasses [of water] per 24 hours, and this can be in the form of coffee, tea, milk, soft drinks, beer, etc. Fruits and vegetables are also good sources of water.”
This passage wasn’t referenced, and seems to have reflected the opinions of the authors rather than any scientific evidence, but after it was cited in an obituary following Stare’s death in 2002, it garnered renewed attention. Could it be that this was the beginning of a worldwide obsession with hydration?
Beating me to it, a few years ago a Scottish doctor debunked the recommendations in an article in the British Medical Journal; calling the idea of needing to drink eight glasses a day ‘nonsense,’ and suggesting these claims benefitted only the bottled water industry.
The fact is, drinking water is not the only source of hydration our body receives. All food we consume contains water in it; indeed, some fruits and vegetables are over 95% H2O. Even the driest of foods contain a proportion of water, and according to the National Health and Medical Research Council, solid food contributes to around 20% of our daily water needs. Further to this, all fluids we consume make a difference – that includes juice, milk, and even tea and coffee, whose diuretic effects have been shunned of late, with studies indicating that they do count towards our daily fluid intake. Add to all this the small proportion of water gained from metabolic processes, and it’s evident that sculling bottle after bottle of Mount Franklin really isn’t as imperative as we’ve been led to believe.
Is it possible drinking too much water could leave us waterlogged?
While its occurrence amongst the general population is rare, a condition called hyponatreamia, which is characterised by a severe drop in cellular sodium levels, can result from over-hydration. In the most serious of cases, this can cause cells to swell, leading to seizures and even death.
Hyponatreamia has been seen in marathon runners, with some tragic deaths resulting from drinking too much water without replacing lost electrolytes. Cases have also been recorded in ecstacy users, in whom an increased production of anti-diuretic hormone (which encourages the kidneys to reabsorb water) can lead to over-hydration. As the drug also causes increased body temperature and involuntary movements, users will often guzzle down water, which in some sad cases has lead to death as a result of quite literally drowning.
And in a case of a joke gone wrong, a 2007 American radio show stunt dubbed ‘Hold Your Wee for a Wii’ led to a shock death from water intoxication. A 28 year old woman answered the show’s seemingly harmless challenge, drinking bottle after bottle of water in the hope of winning a video game, only to die hours later from the excessive fluid intake. These are, of course, rare and tragic circumstances, but they do highlight the importance of awareness.
Keeping hydrated is necessary and easy to monitor, and you’ll be far better served paying attention to what your own body is telling you rather than relying on some magic number. Aside from moderate to severe dehydration, in which headache, dry skin, dizzy or light-headedness may arise, the need for a drink will be evident enough if your urine colour is anything but light or pale straw-coloured.
Categories: fact or fiction