For me it really varies. Sometimes I can eat tortilla chips and sometimes not - at times they go through me just fine, other times as I'm eating them my mouth will start to swell up a bit and then I'll get hit with gut cramps a little while later (at least that way I know, when my mouth starts swelling, I have to stop eating and reach for my heating pad!). I seem to be able to eat frosted flakes cereal (basically corn flakes but covered in sugar) any time, those never bother me - which is weird because it's basically sugar and corn, neither of which is usually easy on me. My mom once gave me some frozen pizza dough made from rice & corn flour, and that was awful on my system, I felt sick for several days after eating that. So for me it seems to vary product to product. In general I try to avoid corn products because it's usually just not worth the risk.