Gastric emptying is a major determinant of glycemia, gastrointestinal hormone release and appetite. We determined the effects of different intraduodenal glucose loads on glycemia, insulinemia, GLP-1, GIP and CCK, antropyloroduodenal motility and energy intake in healthy subjects. Blood glucose, plasma hormone and antropyloroduodenal motor responses to 120 min intraduodenal infusions of glucose at (i) 1 ("G1"), (ii) 2 ("G2"), and (iii) 4 ("G4") kcal/min, or (iv) saline ("control") were measured in 10 healthy males in double-blind, randomized fashion. Immediately after each infusion energy intake at a buffet meal was quantified. Blood glucose rose in response to all glucose infusions (P < 0.05 vs. control), with the effect of G4 and G2 being greater than that of G1 (P < 0.05), but with no difference between G2 and G4. The rises in insulin, GLP-1, GIP and CCK were related to the glucose load (r > 0.82, P < 0.05). All glucose infusions suppressed antral (P < 0.05), but only G4 decreased duodenal, pressure waves (P < 0.01), resulted in a sustained stimulation of basal pyloric pressure (P < 0.01) and decreased energy intake (P < 0.05). In conclusion, variations in duodenal glucose loads have differential effects on blood glucose, plasma insulin, GLP-1, GIP and CCK, antropyloroduodenal motility and energy intake in healthy subjects. These observations have implications for strategies to minimize postprandial glycemic excursions in type-2 diabetes.