Background:We aimed to determine the plausible role of high body mass index (BMI) in the etiopathogenesis of coronary artery disease (CAD), erosive esophagitis (EE) and gastroesophageal reflux disease (GERD) and their complex associations.Methods:The published literature was retrieved from Cochrane, Google Scholar, Embase, PubMed and Scopus databases until August 2021 based on the inclusion and exclusion criteria. The Newcastle-Ottawa quality assessment scale was used for the risk of bias and publication bias with a funnel plot. Heterogeneity between studies underwent evaluation using the I 2 statistic and Q-test, and a random and fixed-effect model analysed studies with low to moderate heterogeneity.Results:Out of 3819 studies extracted, 20 studies were studied based on the inclusion and exclusion criteria. The study corroborated the direct association of GERD symptoms and EE among obese Odds Ratio (OR) = 4.25) and overweight subjects (OR 9.75). Separate analyses of the link between GERD symptoms and EE was conducted among the overweight (OR 4.11, OR 4.61) and obesity subjects was statistically significant (OR 12.07, OR 9.95). The corresponding adjusted OR was noted for the association of CAD with overweight and obesity amounted to 3.41 and 3.01, respectively. Separate subgroup analysis was analyzed based on different ethnic populations for the association between GERD symptoms and EE in obesity (OR of 9.38) and over-weight (OR of 4.21) subjects were statistically significant (P<0.05). For population subgroup analyses the overall OR of 3.32 was noted on the association between CAD and obesity.Conclusion:Moderate to severe BMI has bene considered as an independent risk factor for GERD symptoms, EE and CAD.