INTRODUCTION: Gastroesophageal reflux disease (GERD) and flatulence are both prevalent afflictions and negatively impact the quality of life. This study aims to determine the relationship between the Global Diet Quality Score (GDQS), a novel metric based on the Prime Diet Quality Score with GERD and flatulence in Iranian adults. METHODS: The cross-sectional study was conducted among 6202 adults in the context of the Shahedieh cohort study accomplished. Dietary intakes of participants were collected by food frequency questionnaires (FFQs). To calculate GDQS, 25 food groups were comprised (16 healthy and 7 unhealthy food groups and two food groups categorized as unhealthy when consumed excessively). GERD and flatulence were assessed by a self-reported questionnaire. To examine the association between GDQS with GERD and flatulence, logistic regression was performed in crude and adjusted models (Model I: adjustments for age and energy intake
Model II: gender, physical activity, marital status, occupation, educational levels, WSI, and BMI
and Model III: smoking status, depression, diabetes, hypertension, and cardio events.) RESULTS: Participants in the highest quintile of GDQS had 20% higher odds of having GERD than individuals in the lowest one (OR: 1.20
95% CI: 0.88-1.65, P trend = 0.508). Compared to the lowest quintile, the participants in the highest quintile had no significant reduction in probability of having flatulence in the crude model (OR: 0.94
95% CI: 0.81-1.11, P trend = 0.578). These associations remained non-significant after adjustments for confounding variables. CONCLUSION: No significant associations were observed between higher adherence to GDQS with odds of GERD and flatulence in Iranian adults. To better understand these findings, longitudinal studies especially randomized clinical trials are needed.