Effects of Green Tea on Esophageal Transit and Gastric Emptying in Patients with Heartburn

Abstract

Many patients with gastro-esophageal reflux disease suffer from epigastric discomfort after consuming green tea. Few published reports discuss the effects of green tea on the gastrointestinal tract. The aim of this study is to assess the effects of green tea on esophageal motility and liquid gastric emptying using scintigraphic methods. Seventeen patients with the symptom of heartburn for at least 3 weeks in the past year were enrolled in this study. Quantitative esophageal scintigraphy and liquid gastric emptying study were conducted simultaneously after ingestion of 500mL of glucose water or green tea in glucose water on two consecutive days. Of the seventeen patients, ten have endoscopically documented reflux esophagitis. On esophageal transit study, esophageal transit time was prolonged in eleven of seventeen patients (64.5%) after green tea consumption, but there was no significant difference when compared before with after green tea consumption [6.73 (5.66-9.26) vs. 7.25 (6.03-10.58); p=0.26]. Retrograde index increased in fifteen subjects (88.2%) and this result reached statistical significance [0.13 (0.11-0.20) vs. 0.25 (0.14-0.35); p＜0.01]. Further analysis indicated that the difference is more prominent in the reflux esophagitis group [0.12 (0.11-0.20) vs. 0.31 (0.17-0.35)]. In non-reflux esophagitis group, although no statistical significance, an increase of retrograde index was found in 5 of 7 patients (71.43%). On liquid gastric emptying study, there was no significant change in liquid gastric emptying time [35.30 (27.75-58.28) vs. 38.8 (26.55-58.15); p=0.6]. We conclude that in patients with heartburn green tea consumption did modulate esophageal motor activity, but not liquid gastric emptying. This phenomenon is more prominent in patients with heartburn and evidence of endoscopic reflux esophagitis.