"...if you ask serious nutritionists and scientists where the advice to drink at least eight glasses of water every day came from, they haven't the faintest idea. There is no evidence that drinking this amount of fluid has any health benefits or that it improves skin hydration."

"...Basic physiology shows that the advice to drink eight 8oz glasses a day hugely over estimates our fluid requirements. To replace daily losses of water an average-sized healthy adult needs no more than about a litre a day, equivalent to four 8oz glasses a day. According to most estimates, that's roughly the amount of water we get in solid food. Indeed this is the way the body has been designed to get water - primarily through vegetables and fruit."

"...So, in theory you cover your minimum water requirements without drinking anything (though I certainly don't recommend this)"

" ...fluid intake is closely regulated by one of the most sophisticated of all the body's regulatory systems - the thirst mechanism. This usually kicks in when we have lost 1-2% of total body water. But that loss is not harmful, so there is no argument for continually topping up with water throughout the day."

"...So it seems that the best science is telling us - perhaps surprisingly - what we instinctively know what is right: ie to trust what our bodies are telling us. The thirst mechanism has evolved over millions of years and seems to have served humans very well until now . . .......sipping water throughout the day won't do you any harm, there's no evidence that it will do you any great good.".