Scientists in the United States say there is little evidence that drinking lots of water improves the health.
The scientists from the University of Pennsylvania say that while dehydration can be harmful and can cause serious damage, there is no clear evidence of benefit from drinking increased amounts of water.
Dr. Dan Negoianu, and Dr. Stanley Goldfarb say there is no research supporting the standard recommendation of eight glasses, each containing eight ounces of water (a total of 1.8 litres), a day.
Dr. Negoianu and Dr. Goldfarb who are based at the Renal, Electrolyte, and Hypertension Division of the University reviewed every published clinical study on the topic.
They say while they found evidence that people in hot, dry climates have an increased need for water, as do athletes, as well as people suffering with some diseases, no such data exist for average, healthy individuals.
The scientists say no study advocated that people need to drink the recommended eight glasses of water each day and it is unclear what is the source of that recommendation.
The researchers say though some studies suggested that water intake affects the rate that kidneys clear salt and urea from the body, they failed to show any health benefits.
Other research indicated that water retention in the body varied considerably and depended on the speed with which water is swallowed; drunk quickly, water leaves the body more quickly, but sipped slowly it is more likely to be retained.
However no studies showed any benefit to organs from increased water.
The scientists also examined the premise that drinking more water makes people feel full and helps them loose weight and the research was found to be inconclusive.
Dehydration can be a serious problem and can cause kidney stones and constipation and lead to dangerous concentrations of salts in the blood.
Most people however get all the fluids they need from food, tea, coffee and other drinks and though water has been lauded as an elixir for a variety of reasons there is no clear evidence that drinking more water is healthy.
According to experts the best easiest way of checking for dehydration is through the colour of urine which should be straw coloured.
The research is published in the Journal of the American Society of Nephrology.