first of all- the fact that you ask that question is wonderful!! most parents just give up to junk food just because it's easier. asking that question means you are commited to your daughter's health.
now, about your question, here is a link to a site filled with videos of pediatritions speaking of any problem that might come up. this section is about nutrition:
http://www.thedoctorsvideos.com/categories/26/Nutrition