IS COFFEE A COLONIC STIMULANT

Background It is unclear if ingestion of coffee affects colonic functi on and if this effect is due to its caffeine content. We investigated the effects of coffee on colonic motor activity in healthy humans. Met hods We performed ambulatory colonic manometry by placing a six-sensor solid-state probe up to the midtransverse colon in 12 healthy subject s. The following day, over a 10 h period, subjects received four stimu li: 240 ml of three drinks at 45 degrees C in random order: black Colo mbian coffee (150 mg caffeine), decaffeinated coffee or water and 1000 kcal meal. We analyzed the effects of each stimulant on colonic motor responses. Results Caffeinated coffee, decaffeinated coffee and meal induced more activity in the colon with a greater area under the curve of pressure waves (P < 0.01) and a greater number of propagated contr actions (P < 0.05) when compared with water. Caffeinated coffee, decaf feinated coffee and meal induced greater (P < 0.05) motor activity in the transverse/descending colon when compared with the rectosigmoid co lon. The effects of decaffeinated coffee on colonic motility were not significantly different from those of water or caffeinated coffee and were lower (P < 0.05) than that of a meal. Conclusion Caffeinated coff ee stimulates colonic motor activity. Its magnitude is similar to a me al, 60% stronger than water and 23% stronger than decaffeinated coffee . (C) 1998 Rapid Science Ltd.