Background: The consumption of coffee allegedly induces or aggravates gastrointestinal symptoms. In order to investigate the effect of coffee on gastrointestinal motility we studied the effect of coffee on gastric emptying and oro-caecal transit time.
Methods: In a randomised, controlled, cross-over study gastric emptying and oro-caecal transit time were studied in 12 healthy volunteers, using applied potential tomography and lactulose hydrogen breath test, respectively. After 1 day of coffee abstinence and an overnight fast, coffee or the control drink (water) was drunk and 10 min thereafter a liquid nutrient meal was ingested together with lactulose. During 150 min, recordings were made with applied potential tomography and breath samples were taken every 5 min. Lag-phase duration and gastric half-emptying time were determined by two blinded observers.
Results: The lag-phase duration after coffee (median 19.8 min, range 6-47 min) was not significantly different from that after water (median 19.3 min, range 11-37.5), nor was the gastric half-emptying time (median 75.7 min, range 56-157.6 vs. median 83.4 min, range 64. 6-148.4). Likewise, coffee had no significant effect on oro-caecal transit time (median 135 min, range 60-270 vs. median 140 min, range 55-270). No significant correlation between any of these parameters and mean daily coffee intake was found.
Conclusions: Coffee does not affect gastric emptying of a liquid meal or small bowel transit.