AIM:To investigate the relationship between reflux and body mass index(BMI) in the asymptomatic obese population using the impedance-p H technique.METHODS:Gastroesophageal reflux is frequent in the obese population.However,the relationship between acid reflux and BMI in asymptomatic obese people is unclear.Forty-six obese(BMI > 25 kg/m2) people were enrolled in this prospective study.We evaluated the demographic findings and 24-h impedance p H values of the whole group.Gas,acid(p H < 4),weak acid(p H = 4-7) and weak alkaline(p H ≥ 7) reflux parameters were analyzed.RESULTS:The mean age of patients was 49.47±12.24 years,and half of them were men.The mean BMI was 30.64±3.95 kg/m2(25.14-45.58 kg/m2).BMI of 23 was over 30 kg/m2.Seventeen patients had a comorbidity(hypertension,diabetes mellitus,or ischemic heart disease).Endoscopic examination revealed esophagitis in 13 of the 28 subjects(10Grade A,3 Grade B).The subjects were divided into two groups according to BMI(<30 and>30 kg/m2).Demographic and endoscopic findings,and impedance results were similar in these two groups.However,there was a positive correlation between BMI and total and supine p H<4 episodes(P=0.002,r=0.414;P=0.000,r=0.542),p H<4 reflux time(P=0.015,r=0.319;P=0.003,r=0.403),and De Meester score(P=0.012,r=0.333).CONCLUSION:Acid reflux is correlated with BMI in asymptomatic obese individuals. AIM: To investigate the relationship between reflux and body mass index (BMI) in the asymptomatic obese population using the impedance-p H technique. METHODS: Gastroesophageal reflux is frequent in the obese population. Still, the relationship between acid reflux and BMI in asymptomatic obese people are unclear. Forty-six obese (BMI> 25 kg / m2) people were enrolled in this prospective study. We are evaluating the demographic findings and 24-h impedance p H values ​​of the whole group. Gas, acid (p H < 4), weak acid (p H = 4-7) and weak alkaline (p H ≧ 7) reflux parameters were analyzed .RESULTS: The mean age of patients was 49.47 ± 12.24 years, and half of them were men. Mean BMI was 30.64 ± 3.95 kg / m2 (25.14-45.58 kg / m2). BMI of 23 was over 30 kg / m2.Seventeen patients had a comorbidity (hypertension, diabetes mellitus, or ischemic heart disease). Endoscopic examination revealed esophagitis in 13 of the subjects were divided into two groups according to BMI (<30 and> 30 kg / m2). There was a positive correlation between BMI and total and supine p H <4 episodes (P = 0.002, r = 0.414; P = 0.000, r = 0.542) , P H <4 reflux time. (P = 0.015, r = 0.319; P = 0.003, r = 0.403) and De Meester score (P = 0.012, r = 0.333) .CONCLUSION: Acid reflux is correlated with BMI in asymptomatic obese individuals.