Died from no water

[DrMurdoc 3]

Drank some coke, played 20 more minutes, then I left and came back the next day and no evidence that I had taken a drink, and my coke gone, only found hatchets and died.

[Dingus (DayZ) 429]

Sounds like your character state wasn't saved for some strange reason then. As far as I know, character states are saved every 60 seconds, so eating or drinking, then immediately logging out can result in your character not gaining the effect, but still losing the item. Why it didn't save in 20 minutes, I don't know.

Good luck on your next life though.

[bbilbo1 149]

Did you happen to notice a little red or possibly orange Chain icon on your screen when you were playing?

If so, that meant your client wasn't properly communicating with the server and therefore didn't remember what you did. So when you logged back on, it recalled the last known good data that was stored on the server.