<<Disclaimer: Verify this information before applying it to your situation.>> Comment from Don Kasarda, Albany, CA, on use of xanthan gum and guar gum. I think people who are having problems with the above gluten replacements might find methylcellulose to be a good substitute. A rice bread formula for celiac patients based on methyl cellulose as gluten substitute was developed by Maura Bean of this lab many years ago and the formula seemed to work well. I think EnerG Foods sells the methyl cellulose. It should be a more pure, less complex substance than the natural gums. Consequently, I think it might be less likely to cause allergic reactions or other harmful effects, although I don't personally have any experience with it.