Effect of Pea Fiber Supplementation on the Gut Microbiota and Host Metabolome and Proteome (FIB) (FIB)

Effect of Pea Fiber Supplementation on the Gut Microbiota and Host Metabolome and Proteome

All subjects will complete a 49-day, multi-phase feeding study to evaluate the effect of pea fiber supplementation on gut community structure and features of host biological state (plasma proteome/ metabolome). Subjects will be asked to continue to consume their habitual diet (free diet phase) for 4 days prior to being provided with a diet high in saturated fat (HiSF) and low in fruits and vegetables (LoFV) in the form of packed-out meals and snacks to consume for the following 45 days. Ten days after starting to consume the HiSF-LoFV diet, subjects will supplement their diet with pea fiber for a total of 21 days; the energy contribution from the HiSF-LoFV diet will be reduced accordingly to maintain energy needs during this time. After completing the pea fiber supplementation phase of the study subjects will revert back to consuming the HiSF-LoFV only diet for the final 14 days. Stool, urine and blood will be sampled periodically throughout.

Study Overview

• Status: Completed
• Conditions: Microbial Colonization
• Intervention / Treatment: Other: Low fiber diet; Other: Pea Fiber Bar; Other: Low fiber diet

• Study Type: Interventional
• Enrollment (Actual): 13
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Missouri
    • Saint Louis, Missouri, United States, 63146
      • Tara Wilmot

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 60 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• BMI 25.0-35.0 kg/m²
• Presence of B. vulgatus and B. thetaiotaomicron each at greater than 0.01% relative abundance

Exclusion Criteria:

• Previous bariatric surgery
• Significant organ system dysfunction (e.g. diabetes, severe pulmonary, kidney, liver, or cardiovascular disease)
• Cancer or cancer that has been in remission for less than 5 years
• Major psychiatric illness
• Inflammatory gastrointestinal disease
• Pregnant or lactating women
• Use of medications that are known to affect the study outcome measures
• Use of medications or supplements known to affect composition of the gut microbiota within the last 30 days (e.g. antibiotics)
• Bowel movements less than 3 times per week
• Vegans, vegetarians, and those with allergies, aversions, or sensitivities to foods provided in the study
• Persons that are not able to grant voluntary informed consent
• Persons who are unable or unwilling to follow the study protocol or who the research team deems not an appropriate candidate for the study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Diet intervention; All participants will stay weight stable while undergoing 3 phases of a dietary intervention

Other: Low fiber diet; Participants will be provided with a low fiber diet in the form of packed out meals and snacks for 24 days in total (days 5-14 and days 36-49); Other: Pea Fiber Bar; Participants will be provided with a low fiber diet plus 1-3 daily pea fiber bars from days 15-35; Other: Low fiber diet; Participants will return to the low fiber diet for days 36-49- this phase is the same as phase 1.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in plasma lipid profile as assessed by the complete metabolic panel and lipid panel.	Blood will be drawn for the complete metabolic panel and lipid panel	At screening, day 14, day 35, and day 49
Changes to the gut microbiota as assessed by established culture independent methods, as well as LC-QTOF Mass-Spectometry (MS) and LC-QQQ MS and GC-MS	Frequent stool samples will be collected throughout the entire study	stool samples will be collected from the screening visit through the final day of the 49-day intervention
Changes in urine proteomes and metabolomes as assessed by liquid chromatography	First morning urine samples will be collected periodically throughout the study	Daily or every other day first-morning urine samples will be collected from day 1 to day 49 of the study
Changes in plasma proteomes and metabolomes as assessed by liquid chromatography	fasting blood draws will be collected periodically throughout the study	Fasted blood draws will be collected on days 1, 14, 21, 28, 35, and 49 of the study
Change in hemoglobin A1c (HbA1c) in response to the dietary intervention	Blood will be drawn for the HbA1c	At screening, day 14, day 35, and day 49

Collaborators and Investigators

• Sponsor: Washington University School of Medicine
• Investigators: Principal Investigator: Samuel Klein, MD, Washington University School of Medicine

Study record dates

Study Major Dates

• Study Start (Actual): February 13, 2019
• Primary Completion (Actual): August 30, 2019
• Study Completion (Actual): June 1, 2020

Study Registration Dates

• First Submitted: March 21, 2019
• First Submitted That Met QC Criteria: November 6, 2019
• First Posted (Actual): November 12, 2019

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: December 23, 2024
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Infections; Communicable Diseases
• Other Study ID Numbers: 201812063

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

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