Impact of a Dried Vegetable on Bowel Function and Gut Microbiota (HappYFiber)

The Impact of a Dried Vegetable on Bowel Function and Gut Microbiota in Subjects with Bowel Function Issues

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.

Study Overview

• Status: Recruiting
• Conditions: Bowel Function Dissatisfaction
• Intervention / Treatment: Dietary supplement: Dried chicory root particles; Other: Placebo

Detailed Description

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.

• Study Type: Interventional
• Enrollment (Estimated): 160
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Edith JM Feskens, Prof. dr; Phone Number: +31317482567; Email: edith.feskens@wur.nl
• Study Contact Backup: Name: Sofie CC van der Zalm, MSc; Phone Number: +31618417162; Email: vezel@wur.nl

Study Locations

• Netherlands
  • Gelderland
    • Wageningen, Gelderland, Netherlands, 6708 WE
      • Recruiting
      • Wageningen University & Research, Division of Human Nutrition & Health
      • Contact: Sofie CC van der Zalm, MSc; Phone Number: +31 6 18 41 71 62; Email: sofie.vanderzalm@wur.nl
      • Contact: Marie-Luise Puhlmann, MSc; Phone Number: +31 6 38 03 11 29; Email: marie-luise.puhlmann@wur.nl
      • Contact: Edith JM Feskens, Prof. dr.

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• 20 - 80 years old
• Unsatisfied with bowel functions (self-reported), rated on a visual analogue scale (VAS, 0-10) as less than 6
• Four or less bowel movements per week (low stool frequency) and/or
• Hard, lumpy or solid stools (Bristol stool form 1-4) during 90% of bowel movements (hard to solid consistency)
• 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., IBS or 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 during the screening
  • Chronic use of blood glucose lowering medication
• Consumption of supplements containing fibres (other than laxatives), pro-/ post-/ synbiotics 1 month before the screening
• Not willing to provide faecal 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 greater than 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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Highest fiber dose; 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; The intervention product consists of chicory root that have been sliced and dried and are provided in the form of particles (~3mm).; Other Names: brand name: WholeFiber™
Experimental: Medium fiber dose; 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; The intervention product consists of chicory root that have been sliced and dried and are provided in the form of particles (~3mm).; Other Names: brand name: WholeFiber™
Experimental: Lowest fiber dose; 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; The intervention product consists of chicory root that have been sliced and dried and are provided in the form of particles (~3mm).; Other Names: brand name: WholeFiber™
Placebo Comparator: Control; 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; The control arm receives a placebo consisting of rice puff particles.; Other Names: Rice puff particles

What is the study measuring?

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

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Bowel function (weekly changes) - 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.	Weekly development for a period of 4 weeks
Bowel function (weekly changes) - ease of defecation	Ease of defecation is rated on a five-point scale (from "0-not at all" to "4-extremely").	Weekly development for a period of 4 weeks
Bowel function (weekly changes) - 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").	Weekly development for a period of 4 weeks
Bowel function (weekly changes) - stool consistency	Stool consistency is measured using the Bristol Stool Form Scale (7-point scale from 1=hard to 7=diarrhea).	Weekly development for a period of 4 weeks
Bowel function (weekly changes) - stool frequency	Stool frequency is measured by counting number of bowel movements per week.	Weekly development for a period of 4 weeks
Fecal gut microbiota (weekly changes)	Measured in fecal samples using DNA sequencing.	Weekly development for a period of 4 weeks
Fecal gut microbiota activity (weekly changes)	Fecal gut microbiota activity is determined by measuring microbial metabolites in fecal samples among which fermentation products (short-chain fatty acids) using HPLC.	Weekly development for a period of 4 weeks

Collaborators and Investigators

• Sponsor: Wageningen University
• Collaborators: Wageningen University and Research; WholeFiber BV; Wageningen University and Research, Laboratory of Microbiology; Wageningen University and Research, Division of Human Nutrition & Health
• Investigators: Principal Investigator: Edith JM Feskens, Prof. dr, Wageningen University & Research

Publications and helpful links

General Publications

• Puhlmann ML, de Vos WM. Back to the Roots: Revisiting the Use of the Fiber-Rich Cichorium intybusL. Taproots. Adv Nutr. 2020 Jul 1;11(4):878-889. doi: 10.1093/advances/nmaa025. Erratum In: Adv Nutr. 2021 Jul 30;12(4):1598. doi: 10.1093/advances/nmab082.
• Puhlmann ML, Jokela R, van Dongen KCW, Bui TPN, van Hangelbroek RWJ, Smidt H, de Vos WM, Feskens EJM. Dried chicory root improves bowel function, benefits intestinal microbial trophic chains and increases faecal and circulating short chain fatty acids in subjects at risk for type 2 diabetes. Gut Microbiome (Camb). 2022 Apr 28;3:e4. doi: 10.1017/gmb.2022.4. eCollection 2022.

Study record dates

Study Major Dates

• Study Start (Actual): August 22, 2022
• Primary Completion (Estimated): June 1, 2025
• Study Completion (Estimated): June 1, 2025

Study Registration Dates

• First Submitted: July 11, 2022
• First Submitted That Met QC Criteria: July 21, 2022
• First Posted (Actual): July 26, 2022

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: February 22, 2025
• Last Verified: February 1, 2025

More Information

Terms related to this study

• Keywords: gut microbiota; constipation; bowel function issues; fiber intake; vegetable; intrinsic fiber
• Other Study ID Numbers: NL80274.091.22

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: As the data contains sensitive personal information researchers interested in the data can contact the principal investigator.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No