Impact of a Dried Vegetable on Bowel Function and Gut Microbiota

Study Overview
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Brief Summary
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A randomized, placebo-controlled, parallel, double-blind trial with three intervention arms and a period of four intervention-weeks that assesses the intake of different dosages of a complex fiber product on bowel function via microbiota changes in subjects that are unsatisfied with their current bowel function.

Detailed Description
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Background: Bowel function issues can have a substantial effect on quality of life. Additional fiber intake might modulate bowel function and gut microbiota, thereby increasing stool frequency and consistency. This could improve defecation ease, feeling of incomplete bowel emptying and bowel function satisfaction. We hypothesize that a dried vegetable, that is naturally high in fiber within plant cells could improve bowel function in subjects with bowel function issues. Objective: The main objective of the study is to assess whether a dried multifiber vegetable improves bowel function assessed by stool frequency, consistency, defecation ease, feeling of incomplete bowel emptying and satisfaction. Secondary objectives are to assess whether these effects are dose-dependent and associated with the modulation of the gut microbiota and activity. Furthermore, the adaption of bowel function and adaptation of the gut microbiota and activity over time will be analyzed. Study design: A parallel, randomized, double-blind, placebo-controlled trial of four weeks with one placebo control and three intervention arms that differ in intervention product dose. Study population: Healthy human volunteers, 20 - 80y old, with bowel function issues reflected in low stool frequency/consistency, difficulty to defecate, and dissatisfaction with their current bowel function. Intervention: A vegetable product consisting of dried chicory root cubes containing 85% dietary fiber is added to the daily diet. The intervention product is consumed twice daily for four weeks with a maximum dose of 15 g/day. The control (placebo) consists of easily digestible rice puff particles and is consumed in the same manner as the intervention. Main study parameters/endpoints: Main study outcome are endpoint (week 4) differences from baseline between the highest dose (15 g/day) of the treatment intervention and placebo in bowel function assessed by changes in stool frequency, stool consistency, ease of defecation, incomplete feeling of bowel emptying and bowel function satisfaction. Secondary endpoints are gut microbiota composition and differences in bowel function, quality of life and constipation symptoms assessment between all doses and placebo. Finally, changes over time in gut microbiota and bowel function will be assessed.

Official Title
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The Impact of a Dried Vegetable on Bowel Function and Gut Microbiota in Subjects With Bowel Function Issues

Conditions
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Bowel Function Dissatisfaction

Intervention / Treatment
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* Dietary Supplement: Dried chicory root particles
* Other: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 20 - 80 years old Unsatisfied with bowel functions (self-reported) Four or less bowel movements per week Hard or lumpy stools (Bristol stool form 1-2) during more than 25% of bowel movements Able to read and understand Dutch or English Exclusion Criteria: Having a history of medical or surgical events that may significantly affect the study outcome: e.g., irritable bowel syndrome (IBS) or inflammatory bowel disease (IBD) patients and subjects with medically diagnosed constipation (i.e., constipation related to anatomic, medication-related, or readily identifiable physiological causes.) Less than one bowel movement per week during the screening Medical drug use: Antibiotic use within 3 months of the study screenings day Chronic use of antacids and PPI's Use of laxatives 1 month before the screening Chronic use of blood glucose lowering medication Consumption of supplements containing fibers, pro-/ post-/ synbiotics 1 month before the screening Not willing to provide fecal samples Unable to comply with proper study procedures For women of childbearing age: current or planned pregnancy, lactation Known allergic reactions to plants from the Asteraceae (Compositae) family (e.g., lettuce, daisies, sunflowers, artichokes, sage, tarragon, chamomile, chicory etc.) Reported unexplained weight loss or weight gain of > 5 kg in the month prior to pre-study screening Reported slimming or medically prescribed diet Reported macrobiotic lifestyle Personnel the Division of Human Nutrition & Health or the Laboratory of Microbiology Current participation in other medical scientific research Not having a general practitioner Not willing to be informed about accidental discoveries in relation to the subjects health

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 80 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: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: A randomized, placebo-controlled, parallel, double-blind trial with three intervention arms and one control (placebo) arm.
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Highest fiber dose<br>This arm receives the highest dose of the intervention product, which is 15g dried vegetable per day divided into two portions of each 7.5g, which are consumed during the course of the day in the food of choice. | Dietary Supplement: Dried chicory root particles<br>* The intervention product consists of chicory root that have been sliced and dried and are provided in the form of particles ( 3mm).<br>* Other names: brand name: WholeFiber™;|
| Experimental: Medium fiber dose<br>This arm receives the highest dose of the intervention product, which is 10g dried vegetable per day divided into two portions of each 5.0g, which are consumed during the course of the day in the food of choice. | Dietary Supplement: Dried chicory root particles<br>* The intervention product consists of chicory root that have been sliced and dried and are provided in the form of particles ( 3mm).<br>* Other names: brand name: WholeFiber™;|
| Experimental: Lowest fiber dose<br>This arm receives the highest dose of the intervention product, which is 5g dried vegetable per day divided into two portions of each 2.5g, which are consumed during the course of the day in the food of choice. | Dietary Supplement: Dried chicory root particles<br>* The intervention product consists of chicory root that have been sliced and dried and are provided in the form of particles ( 3mm).<br>* Other names: brand name: WholeFiber™;|
| Placebo Comparator: Control<br>This arm is the control arm receiving as placebo rice puff particles each day, whose amount corresponds iso-calorically to the medium fiber dosage (  21 kcal/day). | Other: Placebo<br>* The control arm receives a placebo consisting of rice puff particles.<br>* Other names: Rice puff particles;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bowel function (differences highest dose vs placebo) - bowel function satisfaction | Bowel function satisfaction is rated on a five-point scale (from 0-not at all to 4-extremely). | Change after the intervention of 4 weeks | 
| Bowel function (differences highest dose vs placebo) - ease of defecation | Ease of defecation is rated on a five-point scale (from 0-not at all to 4-extremely). | Change after the intervention of 4 weeks | 
| Bowel function (differences highest dose vs placebo) - feeling of incomplete bowel emptying | Feeling of incomplete bowel emptying is rated on a five-point scale (from 0-not at all to 4-extremely). | Change after the intervention of 4 weeks | 
| Bowel function (differences highest dose vs placebo) - stool consistency | Stool consistency is measured using the Bristol Stool Form Scale (7-point scale from 1=hard to 7=diarrhea). | Change after the intervention of 4 weeks | 
| Bowel function (differences highest dose vs placebo) - stool frequency | Stool frequency is measured by counting number of bowel movements per week. | Change after the intervention of 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fecal gut microbiota (between dose differences) | Measured in fecal samples using DNA sequencing. Compared between different fiber dosages and placebo. | Change after the intervention of 4 weeks | 
| Fecal gut microbiota activity (between dose differences) | Fecal gut microbiota activity is determined by measuring microbial metabolites in fecal samples among which fermentation products (short-chain fatty acids) using HPLC. Compared between different fiber dosages and placebo. | Change after the intervention of 4 weeks | 
| Quality of Life (between dose differences) | Quality of life is measured using the questionnaire Patient Assessment of Constipation - Quality of Life. Compared between different fiber dosages and placebo. | Change after the intervention of 4 weeks | 
| Constipation-related symptoms (between dose differences) | Constipation symptoms is measured using the questionnaire Patient Assessment of Constipation - Symptoms. Compared between different fiber dosages and placebo. | Change after the intervention of 4 weeks | 
| Bowel function (between dose differences) - bowel function satisfaction | Bowel function satisfaction is rated on a five-point scale (from 0-not at all to 4-extremely). Compared between different fiber dosages and placebo. | Change after the intervention of 4 weeks | 
| Bowel function (between dose differences) - ease of defecation | Ease of defecation is rated on a five-point scale (from 0-not at all to 4-extremely). Compared between different fiber dosages and placebo. | Change after the intervention of 4 weeks | 
| Bowel function (between dose differences) - feeling of incomplete bowel emptying | Feeling of incomplete bowel emptying is rated on a five-point scale (from 0-not at all to 4-extremely). Compared between different fiber dosages and placebo. | Change after the intervention of 4 weeks | 
| Bowel function (between dose differences) - stool consistency | Stool consistency is measured using the Bristol Stool Form Scale (7-point scale from 1=hard to 7=diarrhea). Compared between different fiber dosages and placebo. | Change after the intervention of 4 weeks | 
| Bowel function (between dose differences) - stool frequency | Stool frequency is measured by counting number of bowel movements per week. Compared between different fiber dosages and placebo. | Change after the intervention of 4 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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constipation, gut microbiota, fiber intake, vegetable, intrinsic fiber, bowel function issues