My HG+ DD11 doesn't have any food intolerances per se, but she does have a lot of stomach aches. Last fall they got really bad and she was in tears most days for a few months, so we did a full round of testing and didn't find anything particular. We think that, while it's possible she has some reflux, what it is primarily is that she is very aware of every sensation in her body. So, when she's hungry her stomach hurts, when she's just eaten her stomach hurts, when she's tired her stomach hurts, etc. We did not, however, find any link to stress, despite her doctor being sure that she must be stressed because she's grade skipped. Which is not to say that it's all in her head -- she actually does feel stomach pain. A long course of the right ulcer medication eventually worked to decrease the pain greatly, so there must have been something that caused it, though, even if all the tests were negative.
Anyway, from talking to other relatives, it seems that many of the smarter members of the family have also had this same issue. IMO it's probably part of the general hyper-awareness that a lot of gifted people have of the world around them. (BTW: no 2E issues here.)
But maybe you were wanting to know about actual intolerances and allergies?
