system
A chat on subreddit /r/NoStupidQuestions
human
So what's the real science? Or is just whatever you feel like until you're not thirsty?
gpt
Pretty much exactly that. Drink when thirsty, maybe keep an eye on your pee and drink more if it's getting darker.

And the study about how much to drink that everyone cites? That's total water consumed, which would include water in the food you eat. It didn't actually say to literally drink 8 glasses.