This linked article explains it a bit better IMHO. Coincidentally, some of the largest dietary sources of FODMAPs -- specifically bread products -- are removed when adopting a gluten-free diet, which could explain why the millions of people worldwide who swear by gluten-free diets feel better after going gluten-free. So perhaps what people are searching for are low FODMAP diets. Since a number of other possible irritants (lactose, benzoates, propionate, sulfites, and nitrites) were excluded from the diets, I wonder if part of the NCGS has to do with combinations of irritants, or even interactions between them. Someone might have some ready-mix pancakes, get milk, benzoate, and FODMAPs in one serving, and wrongly attribute their ill-effects to the gluten."Reduction of FODMAPs in their diets uniformly reduced gastrointestinal symptoms and fatigue in the run-in period, after which they were minimally symptomatic."