My healthy child (14) has sufferred from non stop hunger for the last four years. What he eats is simply staggering, but I think that's just part of being a healthy teen. I make sure that what I'm feeding him is healthy and he gets plenty of exercise. He he has no issues at all his weight (very healthy body shape and BMI.)
As long as your daughters diet is healthy, her digestive system is coping with the food intake and her BMI is with in normal range for her age, I don't see constant hunger as a problem.
Like Carolin I'd love to see my younger one have this issue.