I like to think that the water I drink was once inside a T rex.
You’re right, it was. Also Cleopatra, Hitler, Genghis Khan, a trilobite and a pterodactyl, among quite a few other living things.
Did you know: if you take a glass of water, pour it into the sea, give it a decade or two for the molecules to swish about all over the world, and then pick up another glass of seawater, the second glass will absolutely, definitely contain water molecules that were in the first glass. That’s because there are waaaay more water molecules in a glass of water than there are glasses of water in all the world’s oceans (proof). Bonkers. 😀
I still change my Camelbak water every day though, it starts tasting a bit manky after a bit – it’s the stuff that isn’t water that’s the problem.