We studied the rates at which solid and liquid leave the stomach after meals of wholemeal and white bread by using a double isotope technique. There was no difference in the rates at which the solid phases of the gastric contents left the stomach but liquid left the stomach significantly more rapidly with white bread than with wholemeal bread. Furthermore, the amount of liquid leaving the stomach unaccompanied and therefore unbuffered by solid was significantly greater after while bread than wholemeal bread. These findings may be of significance in the pathogenesis of duodenal ulcer and they provide a rational basis for a possible form of dietary treatment.