Effect of Prebiotic Intake on Gut Microbiota in Healthy Adults

In recent years, the importance of the gut microbiota to human health has been demonstrated. In adulthood, the microbial profile is relatively stable, yet can be transiently altered by factors such as diet or antibiotic treatment. Such changes may be beneficial, as gut microbiota has been shown to differ in normal versus disease states including inflammatory bowel disease, obesity, type 2 diabetes and fatty liver disease. Given this relationship, there is intense interest in designing interventions that positively influence the gut microbial profile. Prebiotics are non-digestible, fermentable oligo- and polysaccharides that alter the colonic environment in favour of health-promoting bacterial species, such as bifidobacteria which selectively ferment prebiotics. Given the ability of prebiotics to beneficially alter the microbial profile, there is a need to identify the dosing requirements to positively modulate the gut microbiota. This study will test the effect of two doses of prebiotic on gut microbiota taxonomy and diversity.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Dietary supplement: Control; Dietary supplement: Prebiotic

Detailed Description

The primary objective is to determine the effect of 4 week intake of a moderate dose (7 g/d) or low dose (2.5-3 g/d) of prebiotic on gut microbiota profiles in healthy adults compared to a non-prebiotic containing control.

The primary outcome is change in microbial composition (measured via 16S rRNA sequencing).

The secondary outcomes are change in gastrointestinal (GI) tolerance (measured via questionnaire); change in fecal short chain fatty acids; and change in quality of life.

This study will consist of two separate trials of 12 week duration. Each trial will be performed in a double-blind, randomized, placebo-controlled crossover manner with a 4 week intervention period followed by a 4 week wash-out period and final 4 week cross over.

• Study Type: Interventional
• Enrollment (Actual): 50
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Alberta
    • Calgary, Alberta, Canada, T2N 1N4
      • University of Calgary

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Healthy male and female subjects who are regular snack consumers
• Not obese (BMI ≥ 18.5 kg/m2 and ≤ 29.9 kg/m2)
• 18 and 65 years of age
• Stable bodyweight for at least 3-months prior to the study.

Exclusion Criteria:

• Chronic disease including but not limited to type 1 or 2 diabetes, cardiovascular disease, liver or pancreas disease.
• Major gastrointestinal surgery
• Pregnant or lactating
• Antibiotic use in the preceding 3 months
• Currently consume probiotic or prebiotics supplements
• Currently consume more than 15 g/d of fiber in women and 18 g/d in men
• Are following a diet or exercise regime designed for weight loss
• Have a BMI greater than 29.9 kg/m2.
• Subjects who are required to start an antibiotic regime during the study will be withdrawn.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Control; Isocaloric food without the test prebiotic.	Dietary supplement: Control; Isocaloric food without the test prebiotic.
Experimental: Prebiotic; Prebiotic consumed as one daily serving of 7 g in Group 1 and consumed as one daily serving of 2.5-3 g in Group 2.	Dietary supplement: Prebiotic; Prebiotic consumed as 7 g/d in a snack food in Group 1 and consumed as 2.5-3 g/d in a snack food in Group 2.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in baseline fecal bifidobacteria at 4 weeks	Assessed with 16S rRNA sequencing.	4 weeks in cross-over design

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in baseline fecal short chain fatty acid concentrations at 4 weeks	Analyzed with gas chromatography/mass spectrophotometry	4 weeks in cross-over design
Change in baseline gastrointestinal tolerance at 4 weeks	Analyzed with questionnaire	4 weeks in cross-over design
Change in baseline quality of life rating at 4 weeks	Measured with SF-36 questionnaire	4 weeks in cross-over design

Collaborators and Investigators

• Sponsor: University of Calgary
• Collaborators: General Mills
• Investigators: Principal Investigator: Raylene Reimer, PhD, RD, University of Calgary

Publications and helpful links

General Publications

• Reimer RA, Soto-Vaca A, Nicolucci AC, Mayengbam S, Park H, Madsen KL, Menon R, Vaughan EE. Effect of chicory inulin-type fructan-containing snack bars on the human gut microbiota in low dietary fiber consumers in a randomized crossover trial. Am J Clin Nutr. 2020 Jun 1;111(6):1286-1296. doi: 10.1093/ajcn/nqaa074.

Study record dates

Study Major Dates

• Study Start (Actual): May 15, 2016
• Primary Completion (Actual): May 25, 2017
• Study Completion (Actual): December 31, 2022

Study Registration Dates

• First Submitted: February 1, 2017
• First Submitted That Met QC Criteria: February 1, 2017
• First Posted (Estimate): February 3, 2017

Study Record Updates

• Last Update Posted (Actual): May 9, 2023
• Last Update Submitted That Met QC Criteria: May 8, 2023
• Last Verified: May 1, 2023

More Information

Terms related to this study

• Keywords: Gastrointestinal tolerance; Prebiotic; Gut microbiota; Dietary fiber
• Other Study ID Numbers: REB16-0388

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No