This stood out to me because of how specific the claim being made is. It seems to really only fit a certain demographic, there are factors like weight that should be taken into account because some people need more and some people need less. I did a web search on how much water someone should drink in a day and found that on the website www.mayoclinic.org under the article "Water: How much should you drink every day?" it states that, "Studies have produced varying recommendations over the years. But your individual water needs depend on many factors, including your health, how active you are and where you live. No single formula fits everyone. But knowing more about your body's need for fluids will help you estimate how much water to drink each day." Therefore, the claim being made is exaggerated and not entirely true.