Effect of decaffeination of coffee or tea on gastro‐oesophageal reflux

SUMMARY Background: Coffee and tea are believed to cause gastrooesophageal reflux : however, the effects of these beverages and of their major component, caffeine, have not been quantified. The aim of this study was to evaluate gastro‐oesophageal reflux induced by coffee and tea before and after a decaffeination process, and to compare it with water and water‐containing caffeine. Methods: Three‐hour ambulatory pH‐metry was performed on 16 healthy volunteers, who received 300 ml of (i) regular coffee, decaffeinated coffee or tap water (n = 16), (ii) normal tea, decaffeinated tea, tap water, or coffee adapted to normal tea in caffeine concentration (n= 6), and (iii) caffeine‐free and caffeine‐containing water (n= 8) together with a standardized breakfast. Results: Regular coffee induced a significant (P < 0.05) gastro‐oesophageal reflux compared with tap water and normal tea, which were not different from each other. Decaffeination of coffee significantly (P < 0.05) diminished gastro‐oesophageal reflux, whereas decaffeination of tea or addition of caffeine to water had no effect. Coffee adapted to normal tea in caffeine concentration significantly (P < 0.05) increased gastro‐oesophageal reflux. Conclusions: Coffee, in contrast to tea, increases gastrooesophageal reflux, an effect that is less pronounced after decaffeination. Caffeine does not seem to be responsible for gastro‐oesophageal reflux which must be attributed to other components of coffee.