Cornmeal?

So I was on a fb celiac page for about 45 seconds (how is fb so...angry....?) Anyway, I digress. I noticed someone commented that apparently we shouldn't eat cornmeal, like the main ingredient found in cheezies and cheese puffs, etc. Is that a common thing? I haven't heard anyone say anything about cornmeal so far. It also makes me wonder if there are other products we shouldn't eat that I haven't thought of.