How young is too young?

firesoforion

I'd say it's ok once they're 15 or 16. Before then, focus on feeding them healthy foods. Kids need food to grow, and it's not exactly predictable how much they'll need. As long as it's healthy, though, don''t worry about calories. Once they're 15 or 16 then you can choose whether it's necessary.

NaomsIrl

It depends on the maturity of the individual, but personally I think anywhere below 13 is too young.