Effect of coffee on human lower oesophageal function.

The effect of coffee on lower oesophageal sphincter pressure (LOSP) and intraoesophageal pH was assessed in 10 healthy volunteers, in the fasting state and after a standard Lundh test meal. LOSP was measured by the rapid pull-through technique. Coffee with or without milk has no significant effect on LOSP in the fasting subject. The Lundh meal alone (mean drop = 2.01 cm H2O), or when coffee with (mean drop = 1.80 cm H2O) or without milk (mean drop = 3.47 cm H2O) was taken after it, produced a significant drop in LOSP. Heartburn following coffee does not appear to be due to an effect of coffee on the lower oesophageal sphincter but is more likely due to the effect of a previous meal on sphincter pressure with associated acid reflux.