I heard somewhere that kids, if left to their own nutritional urges, will quickly gravitate toward foods that are actually beneficial to their own nutrition.
I am, however, saddened by the apparent disappearance of that old reality experiment in the UK from Youtube, where we got to see those girls all owning up to their own devices in a big house, both positive and negative. I'm practically teary-eyed over the disappearance of my little cutie-pie who was all about singing songs about boys wanting to touch her chest, and then jumping exuberantly into daddy's arms at the end of it all.
Ah, well, I think it was from 10 or 15 years ago. Loved it. Highly recommended if you can still find it anywhere:)