When people say allergy with wheat, they usually mean gluten intolerance, but some are truly allergic. Most of us are intolerant. You don't get a typical allergic reaction like hives, but you don't completely digest the protein. And those proteins cause your body to mount an immune defense which leads to leaky guy, then those partly digested proteins get into the bloodstream and can cause immune reactions just about anywhere in the body.

In "Dangerous Grains" the author mentioned that the partly digested proteins resemble opiates in structure and do cause some people to get a nasty addiction. This one little boy (celiac) I saw on TV would absolutely cram wheat stuff in his mouth and then zone out. Looked like he had gotten a fix.

I could eat absolutely enormous amounts of wheat. I can't really do that with any other starch.