Dr. Berg goes through the 5 lies about drinking more water. It is one of those “everyone knows”, so drink when you are thirsty. Hyponatremia is a condition whereby you can get really sick by drinking too much water.
“Adolph EF. The regulation of the water content of the human organism. J Physiol (London). 1921;55(1-2):114-32”
In short, the author measured his own urine and sweat output and determined he lost 3 percent of his body weight in water per day, which came out to be eight cups. Based on this, for a long time the water requirement guidelines were eight cups. However, this is not the case anymore except that most people still know the saying: eight glasses of water a day.
“Vivanti AP. Origins for the estimations of water requirements in adults. Eur J Clin Nutr. 2012;66(12):1282-9.”
When you drink too much plain water, your electrolytes no longer can balance the exchange of fluid inside and outside the cell. This causes parts of your cells to swell and others to dehydrate (due to loss of salt).
Also, realize what you input doesn’t equal what you output. If you drink a glass of water, you do not urinate a glass of water. You will urinate a glass full of urine, which is filled with electrolytes and other stuff. So urine is flushing out minerals.