Low fermentable oligosaccharides, disaccharides, monosaccharides and polyols diet is associated with increased risk of uninvestigated chronic dyspepsia and its symptoms in adults.

Background: Assessing the potential effects of a low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) diet on functional gastrointestinal symptoms, particularly upper gastrointestinal symptoms, is not clearly understood. The current study aimed to explore the association of a diet low in FODMAPs with uninvestigated chronic dyspepsia (UCD) and functional dyspeptic symptoms in a large population of Iranian adults.

Methods: This cross-sectional study was conducted on 2987 adults. Dietary FODMAPs intake estimated using a validated food-frequency questionnaire. UCD, early satiation, postprandial fullness and gastric pain were determined using a modified and validated version of the Rome III Questionnaire.

Results: After controlling for various confounders, consumption of a diet low in FODMAPs was associated with increased risk of UCD in the whole population (OR=1.85; 95% CI: 1.23-2.78; P=0.009) and women (OR=2.41; 95% CI: 1.46-3.95; P=0.004), but not in men. Higher consumption of a low-FODMAPs diet was related to increased risk of postprandial fullness (OR=1.38; 95% CI: 1.08-1.78; P=0.046). The inverse association between FODMAPs and epigastric pain tended to be significant after controlling for eating behaviors (OR=1.31; 95% CI: 0.98-1.76; P=0.084). No significant association was observed for early satiation.

Conclusions: Our data suggest that consumption of a low-FODMAPs diet may increase the risk of UCD and postprandial fullness; however, well-planned randomized controlled trials and prospective cohorts are required to ascertain the effect of FODMAPs on upper gastrointestinal symptoms.