Exercise physiologist Stacy Sims, Ph.D ., a hydration researcher at Stanford University states that the often recommended fluid intake of two liters (or eight glasses) a day has no scientific basis and does not take into account factors such as gender, fitness level, environment, or altitude. Therefore, it is possible for one to be in danger of hyponatremia (a condition when sodium in blood becomes too diluted with water) because of too much drinking.
Symptoms of hyponatremia include confusion, headache, bloating, and these can also be confused as symptoms of dehydration. Severe hyponatremia can lead to seizures, organ failure and even death. Sims warns that taking too much “rehydration” drinks which have a high level of sugar and additives may ironically cause dehydration. On the other hand, drinking too much water at once can cause too much urination, and not absorbing any fluid.
Sims suggests some ways to get properly hydrated, starting from not relying solely on thirst, but trying some habits like weighing daily to see that one’s weight does not fluctuate too much. One should also observe the volume and color of urine, especially in the morning, when it should be in copious amounts and pale or clear. One should also wake up not feeling thirsty and must start the day by sipping fluids, instead of guzzling a few glasses fast.
Sims also advises taking fluids other than water during the day, but to watch out for drinks with too much sugar. He also reminds one to count coffee and tea drinking, as well as eating juicy fruits and vegetables which can affect one’s state of hydration.
Rosenbaum, L. Are You Overhydrated? Fitbie.