There are so many reasons to drink a ton of water, my favorites being that it flushes out my system and makes me feel healthier, and it makes me feel full so I don't eat as much.
I've given myself a new rule at work on the weekends concerning beverages, because my not being a morning person leads me to drink a LOT of coffee. A lot. Like jumping around with eyes wide by the afternoon a lot.
I can start with a cup of coffee, but I now have to drink a full 32 oz water bottle before each additional cup of coffee.
I have had to pee a lot lately.

