American Journal of Clinical Nutrition, Vol 27, 91-95, Copyright © 1974 by The American Society for Clinical Nutrition, Inc.

Site of glucose absorption from the intestine of Zambian African subjects

¹ From the Department of Medicine, The University of Zambia, P.O. Box RW110, Lusaka, Zambia

Blood glucose and plasma insulin concentrations have been measured during 2-hr intrajejunal and intravenous infusions of a 278 mmole 1^–1 glucose solution, given at a constant rate of 12.0 ml min^–1, in six Zambian African subjects who had no clinical evidence of malnutrition or of small intestine disease. The jejunal infusions were made at 25 to 61 (mean 46) cm past the ligament of Treitz.

In the subject in whom the jejunal infusion was made at 25 cm, the blood glucose concentration showed a marked increase, and the plasma insulin concentration during the latter part of the infusion exceeded that during the intravenous infusion. In all of the other subjects, both glucose and insulin concentrations were lower during the jejunal than intravenous infusions. In the two subjects in whom the jejunal infusion was made at more than 50 cm past the ligament of Treitz, there were flat glucose and insulin curves during the jejunal infusions compared with those during the intravenous infusions.

The results indicate that in Zambian African subjects, glucose absorption takes place over a limited segment of jejunum; with the technique used, little glucose absorption seems to be possible at 50 cm or more past the ligament of Treitz. This observation may have nutritional importance.