The Effect of Duodenal, Ileal or Combined Infusion of Tastants on Food Intake

Study Overview
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Brief Summary
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Rationale: The appearance of tastants in the small intestine can result in the activation of a negative feedback mechanism from different parts of the intestine to the stomach, the small intestine and to the central nervous system. These processes inhibit food processing, appetite sensations and food intake, and furthermore they increase feelings of satiety and satiation. The effects of intraduodenal and/or intraileal infusion of a combination of tastants (sweet (rebaudioside A), bitter (quinine) en umami (monosodium glutamate(MSG))) and placebo on ad libitum food intake, satiation and gastrointestinal symptoms will be investigated. Objective: To investigate the effect of intraduodenal, intraileal and combined infusion of a combination of tastants versus infusion of placebo on food intake. Secondary objectives: To compare the effect of intraduodenal versus intraileal versus combined intraduodenal and intraileal delivery of a combination of tastants on satiation. To assess the effect of intraduodenal and/or intraileal delivery of a combination of tastants on gastrointestinal symptoms/complaints.

Official Title
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The Effect of Duodenal, Ileal or Combined Infusion of Tastants on Food Intake

Conditions
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Obesity

Intervention / Treatment
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* Dietary Supplement: Tastants duodenal
* Dietary Supplement: Tastants ileal
* Dietary Supplement: Placebo duodenal
* Dietary Supplement: Placebo ileal


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Based on medical history and previous examination, no gastrointestinal complaints can be defined. Age between 18 and 65 years. This study will include healthy adult subjects (male and female). Women must be taking contraceptives. BMI between 18 and 25 kg/m2) Weight stable over at least the last 6 months Exclusion Criteria: History of severe cardiovascular, respiratory, urogenital, gastrointestinal/ hepatic, hematological/immunologic, HEENT (head, ears, eyes, nose, throat), dermatological/connective tissue, musculoskeletal, metabolic/nutritional, endocrine, neurological/psychiatric diseases, allergy, major surgery and/or laboratory assessments which might limit participation in or completion of the study protocol. The severity of the disease (major interference with the execution of the experiment or potential influence on the study outcomes) will be decided by the principal investigator. Use of medication, including vitamin supplementation, except oral contraceptives, within 14 days prior to testing Administration of investigational drugs or participation in any scientific intervention study which may interfere with this study (to be decided by the principle investigator), in the 180 days prior to the study Major abdominal surgery interfering with gastrointestinal function (uncomplicated appendectomy, cholecystectomy and hysterectomy allowed, and other surgery upon judgement of the principle investigator) Dieting (medically prescribed, vegetarian, diabetic, microbiological, biological dynamic) Pregnancy, lactation Excessive alcohol consumption (>20 alcoholic consumptions per week) Smoking Weight <60kg Non-tasters of sweet, bitter or umami Evidence of MSG-hypersensitivity or Chinese restaurant syndrome

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Duodenal tastants, ileal placebo<br>Duodenal infusion of combination of tastants (sweet, bitter and umami), ileal infusion of placebo (tap water) | Dietary Supplement: Tastants duodenal<br>* Duodenal infusion of combination of tastants (sweet, bitter and umami)<br>Dietary Supplement: Placebo ileal<br>* Ileal infusion of placebo (tap water)<br>|
| Experimental: Duodenal placebo, ileal tastants<br>Duodenal infusion of placebo (tap water), ileal infusion of combination of tastants (sweet, bitter and umami) | Dietary Supplement: Tastants ileal<br>* Ileal infusion of combination of tastants (sweet, bitter and umami)<br>Dietary Supplement: Placebo duodenal<br>* Duodenal infusion of placebo (tap water)<br>|
| Experimental: Duodenal tastants, ileal tastants<br>Duodenal infusion of combination of tastants (sweet, bitter and umami), ileal infusion of combination of tastants (sweet, bitter and umami) | Dietary Supplement: Tastants duodenal<br>* Duodenal infusion of combination of tastants (sweet, bitter and umami)<br>Dietary Supplement: Tastants ileal<br>* Ileal infusion of combination of tastants (sweet, bitter and umami)<br>|
| Placebo Comparator: Duodenal placebo, ileal placebo<br>Duodenal infusion of placebo (tap water), ileal infusion of placebo (tap water) | Dietary Supplement: Placebo duodenal<br>* Duodenal infusion of placebo (tap water)<br>Dietary Supplement: Placebo ileal<br>* Ileal infusion of placebo (tap water)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ad libitum meal intake | Difference in ad libitum meal intake (as measured during ad libitum pasta meal) at end of the test day. | 5 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Satiation | Difference in satiation (as measured by VAS) per time point. | 5 weeks | 
| GI-symptoms | Difference in gastro-intestinal symptoms (as measured by VAS) per time point. | 5 weeks |