Effect of Nonabsorbed Amounts of a Fructose–Sorbitol Mixture on Small Intestinal Transit in Healthy Volunteers

Abstract

Although malabsorption of small amounts of fructose–sorbitol mixtures occurs frequently in healthy humans, insights into their effects on gastrointestinal motility are poor. The present study addresses the hypothesis that malabsorption of a fructose–sorbitol challenge changes the small intestinal transit rate. Eleven healthy volunteers participated in a double-blind crossover investigation. In random order, the subjects ingested 30 g glucose or a mixture of 25 g fructose and 5 g sorbitol as 10% solutions. As a radiolabeled marker, ^99mTc-diethylenetriaminepentaacetic acid was added to each test solution. Breath hydrogen and methane concentrations and gastrointestinal progress of the radiolabeled marker were followed for the next 6-hr period. Malabsorption of small amounts of the fructose–sorbitol mixture was evident in all subjects. The area under the gastric radioactivity–time curve after ingestion of glucose did not differ from that after ingestion of the fructose–sorbitol mixture (P = 0.7897). However, the mouth-to-cecum transit of the radiolabeled marker was faster (P = 0.0033) and the percentage content of the marker in colon was higher after ingestion of the fructose–sorbitol mixture than after ingestion of glucose (P = 0.0128). In healthy humans, malabsorption of small amounts of a fructose–sorbitol mixture accelerates small bowel transit.