Free fatty acids have more potent effects on gastric emptying, gut hormones, and appetite than triacylglycerides

Copyright © 2007 AGA Institute Published by Elsevier Inc.Background & aimsThe effects of fat on gastric emptying (GE), gut hormones, and energy intake are dependent on digestion to free fatty acids (FFAs). In animals, small intestinal oleic acid inhibits energy intake more potently than the triacylglyceride (TG) triolein, but there is limited information about the comparative effects of FFA and TG in human beings. We compared the effects of FFA and TG on GE, gut hormone secretion, appetite, and energy intake in healthy males.MethodsNine men (age, 23 +/- 2 y; body mass index, 22 +/- 1 kg/m(2)) were studied on 3 occasions to evaluate the effects of (1) 40 g oleic acid (FFA, 1830 kJ), (2) 40 g macadamia oil (TG, 1856 kJ; both 600-mL oil-in-water emulsions stabilized with 4% milk protein and labeled with 15 MBq (123)I), or (3) 600 mL 4% milk protein (control, 352 kJ), administered intragastrically, on GE, plasma cholecystokinin (CCK) and peptide-YY (PYY) levels, appetite perceptions, and subsequent energy intake.ResultsGE of FFA was much slower than that of TG (P ConclusionsFFAs empty from the stomach more slowly, but stimulate CCK and PYY and suppress appetite more potently than TG in healthy human beings.Tanya J. Little, Antonietta Russo, James H. Meyer, Michael Horowitz, Douglas R. Smyth‡, Max Bellon‡, Judith M. Wishart, Karen L. Jones and Christine Feinle-Bissethttp://www.elsevier.com/wps/find/journaldescription.cws_home/623297/description#descriptio