by Emine Saner Guardian 23 July 2011
An article in the Guardian said:
We’ve been told to drink at least eight glasses a day. Celebrities clutch bottles like fashion accessories and children are urged to swig in class. But as Nigella Lawson is outed as an ‘aquaholic’, is the tide finally turning on the health benefits of H20?
The British Medical Journal’s website had an advert for a new public health initiative, Hydration for Health. It was sponsored by Danone – which owns the Evian, Volvic and Badoit bottled water brands. It urged healthcare professionals to encourage people to drink more water, claiming that “evidence is increasing that even mild dehydration plays a role in the development of various diseases”.
The BMJ admitted “we hadn’t followed our own guidelines. The advertisement bypassed our editorial checks”
The drive to get people to drink more water is everywhere – the Royal College of Nursing’s “hydration toolkit” best practice guidance is produced in conjunction with Water UK, which works on behalf of the water industry. This claims that by drinking water you “will also be helping to protect yourself against three of the biggest killer cancers [bowel, breast and prostate]”.
We’re told to drink lots of water all the time. Dominic Lawson outed his sister Nigella as an “aquaholic”, drinking several litres a day. Everyone carries bottles of water – schoolchildren to executives.
Stanley Goldfarb, professor of medicine and a kidney specialist at the University of Pennsylvania. He said: “When we need water, the brain releases a hormone in response to dehydration that tells the kidney to reduce its excretion of water. The body has this system for regulating amounts of water. The way you’re told to drink water is you become thirsty, and you become thirsty well before there’s any impairment that dehydration might induce.”
He reviewed the medical evidence for drinking water, and debunked some myths.
“One was that water improves your skin,” he says. “We showed there was no scientific basis for that. The second myth is that drinking water is an aid to diets and would reduce your appetite. That has been carefully studied and it doesn’t. If you flavour the water, that will suppress your calorific intake during the subsequent meal, but nobody has shown that it suppresses it over 24 hours. When you finish the meal and you didn’t eat enough calories, you’re going to be hungry, and you’ll eat later. We said there really is no evidence that going on a water-drinking campaign will lead you to lose weight.”
Many of us have been led to believe that the more we drink, the healthier we will be. At the weekend, in his column for the Sunday Times, Dominic Lawson outed his sister Nigella as an “aquaholic”, drinking several litres a day. Several newspapers followed this up this week by interviewing women who drank excessive amounts of water thinking they were doing themselves good – one, Joanne Jarvis, interviewed by the Daily Mail, was hospitalised after drinking 11 litres over four hours.When did we become so fearful of dehydration? Schoolchildren are encouraged to take bottles of water into classrooms and sip them throughout the day. Peer into most meeting rooms in the country and you will see bottles of water planted on the table in front of executives, as if they fear that the slightest dehydration will impair them in some way. At the gym, people replenish water as fast as they sweat it out.
A few years ago, Stanley Goldfarb, professor of medicine and a kidney specialist at the University of Pennsylvania, noticed a strange phenomenon. “People were dragging around big bottles of water with them and drinking all the time and I thought: ‘What are they doing?'”
He says on the phone from his office in Philadelphia: “Since we have a perfectly good system to alert us if we need water, why would you need to subvert that by drinking in a prophylactic way?” He reviewed the scientific literature on the health benefits of drinking a lot of water, identifying the four recurrent themes that were put about by those who advocated it.
“One was that water improves your skin,” he says. “We showed there was no scientific basis for that. The second myth is that drinking water is an aid to diets and would reduce your appetite. That has been carefully studied and it doesn’t. If you flavour the water, that will suppress your calorific intake during the subsequent meal, but nobody has shown that it suppresses it over 24 hours. When you finish the meal and you didn’t eat enough calories, you’re going to be hungry, and you’ll eat later. We said there really is no evidence that going on a water-drinking campaign will lead you to lose weight.”
The third myth he looked at is that drinking water flushes more toxins out of your body. “All it does is increase the volume of your urine, but it doesn’t change the material in the urine. The last issue that people have advocated is that water can control headaches. It was not substantiated.”
When we need water, he says, the brain releases a hormone “in response to dehydration that tells the kidney to reduce its excretion of water. This hormone is suppressed whenever there is more water than the body needs, and the kidney immediately unleashes its ability to excrete water, which is dramatic. The body has this system for regulating amounts of water. The way you’re told to drink water is you become thirsty, and you become thirsty well before there’s any impairment that dehydration might induce.”
“What people don’t need to do is take in two extra litres a day. You’re going to take in two litres a day based on your diet and thirst sensation. What [bottled water companies] are really asking people to do is take in four or five litres, because they’re already taking in two or three as coffee, tea, soft drinks, fruit, alcoholic beverages – that’s all water. This notion is a marketing ploy.”
He also said: “The National Academy of Sciences in the United States did a very extensive study several years ago assessing water intake. Their executive summary was: drink when you’re thirsty.”
The death of the British teenager Leah Betts in 1995 was caused by the huge amount of water she drank after taking an ecstasy pill.
We cover this in detail in WaterDrive.
YouDrive thinks…
There’s a lot to take in here. It really does show that you can’t believe everything you read!
Many things count as liquids and will prevent dehydration – even those we think of ‘diuretics’ which are supposed to dehydrate you.
