Whats the ratio for maintanence (sp) calories per pound of bodyweight?

[emptywallet]

Whats the ratio for maintanence (sp) calories per pound of bodyweight? Like lets say you weighed 150 pounds or whatever. How many calories a day would you need a day to maintain that weight? I know how active you are comes into play, like how much exercising you do, but itsnt there some sort of guideline. My younger brother wants to get started with a nice diet and I'm trying to help him out. I should know this myself but I don't. Anyone?