A new study may explain why people who do not have celiac disease or wheat allergy nevertheless experience a variety of gastrointestinal and extra-intestinal symptoms after ingesting wheat and related cereals.
“Our study shows that the symptoms reported by individuals with this condition are not imagined, as some people have suggested,” said study co-author Peter H. Green, MD director of the Celiac Disease Center. “It demonstrates that there is a biological basis for these symptoms in a significant number of these patients.”

Source: Biological explanation for wheat sensitivity found: Weakened intestinal barrier, systemic immune activation may explain symptoms in people without celiac disease — ScienceDaily