Xylitol vs glucose: effect on the rate of gastric emptying and motilin, insulin, and gastric inhibitory polypeptide release

The effect of xylitol and glucose on the rate of gastric emptying and intestinal transit and on motilin, gastric inhibitory polypeptide (GIP), and insulin release were studied in human volunteers. A single oral dose of 200 mL water containing 30 g glucose or 30 g xylitol, mixed with a 99mtechnetium-tin (99mTc-Sn) colloid, was used. Similar dosing without the label was used in motilin, GIP, and insulin studies. Xylitol decreased the rate of gastric emptying but concomitantly accelerated intestinal transit compared with glucose. The half-times for gastric emptying were 77.5 +/- 4.6 and 39.8 +/- 3.4 min after ingestion of xylitol and glucose solutions, respectively. Glucose suppressed motilin and stimulated GIP secretion; xylitol stimulated motilin secretion but had no effect on GIP, which is currently the main candidate for the role of enterogastrone. The accelerated intestinal transit and increase in plasma motilin observed after xylitol ingestion were thought to be causally related to the diarrhea and gastrointestinal discomfort produced by it.