It flushes out my body, and it's good for my skin. At the same time, some nutritionists insist that half the country is walking around dehydrated. Not at all, doctors say. This unquestioned rule is itself a question mark.
Most nutritionists have no idea where it comes from.
To replace daily losses of water, an average-sized adult with healthy kidneys sitting in a temperate climate needs no more than one liter of fluid, according to Jurgen Schnermann, a kidney physiologist at the National Institutes of Health. One liter is the equivalent of about four 8-ounce glasses. In short, though doctors don't recommend it, many of us could cover our bare-minimum daily water needs without drinking anything during the day. This is flat wrong. Caffeine does cause a loss of water, but only a fraction of what you're adding by drinking the beverage.