well i don't know about HFCS as a trigger for myself... but i do know that garlic powder is the #1 WORST thing i can eat. (well, aside from beans or something, but they're pretty easy to avoid!) and garlic powder, much like HFCS seems to be in EVERYTHING. (including many recipes in the IBS cookbook!) not only does it turn my stomach into a horrible wreck, i get awful headaches from it. my mom's the same way. it doesn't bother me in stuff like ketchup, cause i don't make a meal out of ketchup, but it's so frustrating cuz nearly every time i order grilled or steamed fish at a restaurant thinking i'll be safe, it comes with some nasty spice rub that is loaded w/ garlic powder or garlic salt. fortunately, i can tolerate a small bit of fresh garlic, cause it is tasty, but it has to be VERY fresh garlic. even an old garlic bulb that's been sitting in the veggie bowl too long will mess me up.