Drinking enough amounts of water is very essential for an individual. One probably does not need to drink eight glasses of water a day, says a leading physiologist. We've been led to believe that we should drink about two litres of water a day that's eight glasses of volume eight ounces (the 8 by 8 rule). But, water balance expert Dr Heinz Valtin of Dartmouth Medical School, there is no real scientific evidence for this advice.
Physiologists have long advised that you should consume one millilitre of water for each calorie of food you take in. That leads to a figure of about two and a half quarts a day (64 to 80 ounces which is roughly 8 by 8, as stated above). Dr Heinz Valtin of Dartmouth Medical School, feels that lot of this water in food, points out think about it - how many foods are totally lacking in moisture? To the contrary to conventional wisdom - experiments show that caffeine-containing drinks also contribute to water balance as do weak alcoholic drinks like beer.
Drinking 8 by 8 could even be dangerous or unhealthy. Water, believe it or not, can be intoxicating. If you drink more than you can excrete, your brain could swell - as has happened to athletes and people taking the drug Ecstasy. Frequent urination is another problem. And there's no evidence that those who don't follow the 8 by 8 rule are unhealthy.
There are exceptions, however, says Dr Valtin. You should make sure you drink plenty of water during strenuous physical activity, on long haul flights, and in hot weather. Otherwise, there is no need to look to eight glasses of water a day to keep from dehydration.