Explain how water levels in the body influence the thirst cycle; Identify the main ... Additionally, each day about the same volume (2500 mL) of water leaves the body by ... the body; they conserve water if you are dehydrated, and they can make urine more ... The person should (and normally does) respond by drinking water.
I would tell him that other foods give you vitamin A other than carrots and he probably gets the recommended amount of vitamin A without knowing it, or he could just eat another carrot if he's that worried about it.
