Obesity is a growing epidemic and bariatric surgery has been shown to be the most effective and efficient mean of achieving significant and sustainable weight loss in morbidly obese individuals. Studies have demonstrated that after LSG, between 5 and 30% of patients suffered from GERD, with a small subset of those patients (2.9 %) converting to another bariatric procedure (gastric bypass) because of debilitating GERD symptoms. The investigators propose this current study to examine mucosal impedance before and after sleeve gastrectomy using the novel mucosal impedance procedure, as well as assess quality of life and GERD symptoms parameters. In addition, this study will determine if the level of mucosal impedance pre-sleeve gastrectomy may predict the development of GERD post-surgery. Our Hypothesis is that sleeve gastrectomy is highly associated with the risk of developing new onset GERD. This is a prospective, comparative cohort study. A total of 15 obese patients (BMI ≥ 35) undergoing sleeve gastrectomy by choice will be recruited into the study from our bariatric and weight management program. An initial screening upper endoscopy will be performed as part of pre-bariatric evaluation, during which mucosal impedance will be performed with the consent of the patient. Patients with evidence of erosive esophagitis (LA grade A-D), Barrett's esophagus or eosinophilic esophagitis will be excluded from the study. As per surgical recommendation, PPI will be used for 6 months in all bariatric patients. Six months post-surgery, study patients will be re-evaluated by the GERD symptoms Checklist and SF 36. In addition, their new BMI will be documented. PPI will be held for at least 1 week and a 6 months post-surgical upper endoscopy will be performed to determine the presence or absence of erosive esophagitis and Barrett's esophagus. In addition, esophageal mucosal impedance will be reassessed.