Rubenstein JH, et al. - Since esophageal adenocarcinoma was inversely correlated with ultraviolet radiation exposure, possibly due to vitamin D deficiency or hyperparathyroidism promoting gastroesophageal reflux disease (GERD) and Barrett's esophagus, researchers explored the connection between parathyroid hormone (PTH) and vitamin D deficiency with GERD symptoms, erosive esophagitis, and Barrett’s esophagus. For this investigation, sera from 605 men, including 150 with GERD, 216 with erosive esophagitis, 145 with Barrett's esophagus, and 174 ordinary patients were tested. In contrast to the hypothesis, an inverse connection was found between serum PTH and Barrett’s esophagus. No link was observed between vitamin D deficiency or hyperparathyroidism with GERD symptoms or erosive esophagitis.