Intraduodenal infusion of a combination of tastants decreases food intake in humans.
BACKGROUND
Taste receptors are expressed not only in taste buds but also in the gastrointestinal tract. It has been hypothesized that these receptors may play a role in satiety and food intake.


OBJECTIVE
This study investigated the effect of intraduodenal tastant infusions (bitter, sweet, and umami) on food intake, hunger and fullness, gastrointestinal symptoms, and gastrointestinal peptide release.


METHODS
Fifteen healthy volunteers [6 male; mean ± SEM age: 23.9 ± 2.0 y; mean ± SEM body mass index (in kg/m(2)): 22.4 ± 0.3] received 5 treatments in a double-blind, randomized, placebo-controlled crossover design. Test days started with the insertion of a nasoduodenal catheter followed by a standardized liquid breakfast. Participants received an intraduodenal infusion 150 min after breakfast, containing quinine (bitter), rebaudioside A (sweet), monosodium glutamate (umami), a combination of the 3 tastants, or placebo (tap water) over a period of 60 min. Food intake was measured during an ad libitum meal, and visual analog scales were used to monitor gastrointestinal complaints and hunger and fullness scores. Blood samples were drawn at regular intervals for cholecystokinin, glucagon-like peptide 1 (GLP-1), and peptide YY (PYY) analysis.


RESULTS
Infusion of the combination of tastants substantially decreased food intake (422 ± 97 compared with 486 ± 104 kcal for placebo, P < 0.05), whereas both a combination of tastants and umami decreased hunger scores compared with placebo. No change in cholecystokinin, GLP-1, or PYY concentrations was observed during the infusions. Intraduodenal infusions of the tastants did not result in gastrointestinal symptoms.


CONCLUSIONS
Intraduodenal infusion of umami and a combination of tastants inhibits feelings of hunger, but only the latter also reduces food intake. However, these alterations were not accompanied by changes in the plasma concentrations of the gut-derived peptides cholecystokinin, GLP-1, or PYY. This trial was registered at clinicaltrials.gov as NCT01956838.
Top Institute of Food and Nutrition, Wageningen, Netherlands; Division of Gastroenterology-Hepatology, Department of Internal Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, Netherlands; m.vanavesaat@maastrichtuniversity.nl.
Mark
http://orcid.org/0000-0002-9628-8592
M
van Avesaat
Top Institute of Food and Nutrition, Wageningen, Netherlands; Division of Gastroenterology-Hepatology, Department of Internal Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, Netherlands;
Freddy J
FJ
Troost
Top Institute of Food and Nutrition, Wageningen, Netherlands; The Netherlands Organization for Applied Scientific Research, Zeist, Netherlands; and Division of Human Nutrition, Wageningen University, Wageningen, Netherlands.
Dina
http://orcid.org/0000-0001-7133-5113
D
Ripken
Division of Gastroenterology-Hepatology, Department of Internal Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, Netherlands;
Jelmer
J
Peters
Top Institute of Food and Nutrition, Wageningen, Netherlands;
Henk Fj
HF
Hendriks
Top Institute of Food and Nutrition, Wageningen, Netherlands; Division of Gastroenterology-Hepatology, Department of Internal Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, Netherlands;
Ad Am
http://orcid.org/0000-0001-5819-0116
AA
Masclee
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D062408:Breakfast; D002766:Cholecystokinin / Q000097:blood; D018592:Cross-Over Studies; D045786:Diterpenes, Kaurane / Q000008:administration & dosage*; D004311:Double-Blind Method; D004386:Duodenum / Q000187:drug effects / Q000378:metabolism; D002149:Energy Intake / Q000187:drug effects*; D005260:Female; D005421:Flavoring Agents / Q000008:administration & dosage*; D052216:Glucagon-Like Peptide 1 / Q000097:blood; D006801:Humans; D006815:Hunger / Q000187:drug effects; D008297:Male; D019894:Peptide YY / Q000097:blood; D011803:Quinine / Q000008:administration & dosage*; D012527:Satiation / Q000187:drug effects; D012970:Sodium Glutamate / Q000008:administration & dosage*; D013649:Taste / Q000187:drug effects; D055697:Taste Perception / Q000187:drug effects; D055815:Young Adult
D001786:Blood Glucose; D045786:Diterpenes, Kaurane; D005421:Flavoring Agents; D019894:Peptide YY; D052216:Glucagon-Like Peptide 1; D002766:Cholecystokinin; D011803:Quinine; C025474:rebaudioside A; D012970:Sodium Glutamate
food intake; gastrointestinal peptides; intraduodenal infusion; tastants