The effect of lipid droplet size on satiety and peptide secretion is intestinal site-specific

Background & aims: : Infusion of fat into the small intestine induces satiety. Reducing fat droplet size accelerates fat digestion, but the effect on satiety after ileal fat infusion is not known. The aim of the study was to compare the effects of fat emulsions differing in droplet size (fine, coarse) infused in either duodenum or ileum on satiety, gastric emptying and peptide secretion. Methods: In a randomized single-blind crossover study 15 healthy volunteers received, after intubation with a nasoileal tube, 4 different treatments on 4 consecutive days. After consumption of a liquid meal, 6 g of fine or coarse fat emulsion was infused into duodenum or ileum. Study parameters were satiety, gastric emptying and gut peptides. These parameters were statistically evaluated using ANCOVA. Results: In the duodenum, Fine emulsion significantly reduced hunger, increased fullness, delayed gastric emptying, but did not affect peptide secretion versus Coarse. In the ileum, Fine emulsion did not affect hunger, fullness, or gastric emptying, but significantly increased peptide secretion versus Coarse. Conclusions: Compared to larger fat droplets, smaller droplets significantly affect satiety, gastric emptying and gut peptide release, but with the effect being dependent on the intestinal location of fat delivery. Dutch Trialregister: NTR1515. (C) 2011 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.