What did the media say?
The media reported that the theory that drinking eight glasses of water a day is good for you is a myth.
What did the research show?
The stories are based on an editorial by two kidney specialists writing in the June issue of the Journal of the American Society of Nephrology.
They said there was no ‘solid evidence’ to back the well-established idea that adults should aim to drink eight glasses of water per day – particularly that doing so could clear toxins, keep weight down and improve skin tone.
They carried out a literature review of studies on the subject. They said that, while studies showed drinking water increased clearance of sodium and urea by the kidneys, no clinical benefit from this was indicated. Equally, no benefit to the functioning of other organs was identified, evidence was inconclusive about whether it affected weight gain, and no studies revealed any benefit to skin tone.
They identified one small trial, which found that drinking more water appeared to lead to fewer headaches, but the results were not statistically significant.
What did the researchers say?
The authors Dr Dan Negoianu and Dr Stanley Goldfarb, from the renal, electrolyte and hypertension division at the University of Pennsylvania, said: ‘There is no clear evidence of benefit from drinking increased amounts of water.
‘Although we wish we could demolish all of the urban myths found on the internet regarding the benefits of supplemental water ingestion, we concede there is also no clear evidence of lack of benefit,’ they wrote. ‘In fact, there is simply a lack of evidence in general.’
What does this mean for nursing practice?
The government’s Food Standards Agency recommendation remains that ‘we should drink approximately 1.2 litres – six to eight glasses – of fluid every day to stop us getting dehydrated’.