Effect of sham-feeding on glucose tolerance and insulin secretion

Glucose, 25 g, was infused iv with or without sham-feeding in seven normal males. Sham-feeding improved glucose tolerance, incremental area of blood glucose being 63% (P less than 0.05) of that during iv glucose without sham-feeding. The actual insulin secretion evaluated from the total area under the C-peptide and insulin curves did not differ during iv glucose with or without sham-feeding. These results suggest that the cephalic-vagal reflex improves glucose tolerance during iv glucose, independent of changes in beta-cell function.