I found out the hard way that xanthum gum is not my friend. I made gluten free pizza crust this weekend. It tasted pretty good. I chickened out about making it completely from scratch and purchased a mix. I had a headache Sunday night. Since I hadn't been a model of great eating, I assumed it was from some of the extra crap I ate. All day yesterday I had a migraine. Tonight I had the leftover pizza for dinner on my way to Girl Scouts. Raging headache on the way home. I had no gluten or sugar today, so the common denominator was the gum. I know I can't handle processed foods, so this really isn't a surprise. Xanthum gum apparently is a bacteria combined with corn sugars - why would anyone eat that??? I'll take a gluten reaction over a migraine any day. At least I'm learning. Slowly but surely, I am learning.