Not usually picky where something's okay one day, and then terrible the next, not that I know in person, adult or child.

Though, as a kid, I had the worst time with bananas. I'd either gorge myself on them, or (usually right after my parents caved and bought a ton just for me) be totally sickened by the though of them... probably because they were most of what I'd eaten for the past few weeks.

But it was only bananas.

I'm not criticizing you for the problems you've got. You've got to work around it however it works for you. But I don't think most people *do* have that problem in that severity. (Now I want to go out and poll some several billion people to prove my point. I'm thinking that's a bad idea, though, and very impractical, and not very mature, and I'm sorry.)