Gut Microbial Metabolites of Apple Polyphenols (GutMMAP)

June 17, 2025 updated by: University of Maryland, College Park

Gut Microbial Metabolites Of Apple Polyphenols: Interrogating Individual Differences To Establish Functional Biomarker Utility

The goal of this controlled feeding trial is to learn about the metabolism of polyphenols, a common class of compounds found in plant-based foods, by the gut microbiome. It will evaluate how differences in gut bacteria across individuals influence metabolism of polyphenols from foods, which may influence health benefits that people receive from different foods.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

This is a randomized, cross-over controlled feeding trial. Thirty healthy adult volunteers will be selected to participate on the basis of urinary screening results measuring a gut bacterial metabolite that is produced following consumption of a soy food: 15 O-desmethylangolensin (ODMA) producers and 15 age and gender-matched ODMA non-producers will be included. Participants will be assigned to consume two diets in random order: an apple catechin diet that provides a controlled amount of catechins in apple juice, and a nutritionally-matched low catechin diet. Both diet phases will last 3 days, with a 10 day washout period in between the two diet phases.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
32

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.
  • Name: Margaret Slavin, PhD
  • Phone Number: 301-405-4533
  • Email: mms@umd.edu

Study Locations

  • United States
    • Maryland
      • College Park, Maryland, United States, 20742
        • Department of Nutrition and Food Science

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  1. Completion of informed consent.
  2. Stated willingness to comply with all study procedures and availability for the duration of the study.
  3. Any gender identification, aged 18 - 45.
  4. BMI 18.5 - 40 kg/m^2
  5. Ability to consume the intervention foods and beverages and be willing to adhere to the dietary regimen.
  6. Agreement to provide urine and fecal samples according to the study protocol.
  7. Agreement to adhere to avoid high catechin foods (tea, chocolate) for 4 weeks.
  8. Able to come to the study location for 8 visits according to the study schedule.
  9. As assessed through an initial urine screening phase, a person is eligible either on the basis of (1) the presence of a urinary marker for soy isoflavone metabolism (ODMA), or (2) as a control matched for age and gender.

Exclusion Criteria:

  1. Current, regular use of antacids or acid reducers.
  2. Systemic antibiotic use within the past month prior to the urinary screening until completion of the dietary intervention.
  3. Pregnancy or lactation, within 3 months post-partum (regardless of breastfeeding) at screening or planning to become pregnant during the study duration.
  4. Known allergic reactions to components of the foods or beverages of the study diet (soy, wheat, dairy, peanut, tree nuts, apples, eggs) or any history of anaphylactic food allergy.
  5. Current diagnosis of renal, hepatic, or gastrointestinal conditions.
  6. History of stroke.
  7. Underweight (BMI <18.5 kg/m^2) or severe obesity (BMI >40 kg/m^2).
  8. Under 18 years or above 45 years of age.
  9. Unwilling or unable to participate in the controlled dietary intervention or provide urine or fecal samples.
  10. Has a pacemaker, implanted defibrillator, or other implanted electronic device.
  11. Change of body weight >10% between screening and dietary intervention.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Apple catechin
A 3-day controlled diet
Other: Dietary intervention - apple catechin diet
The intervention will provide a catechin-containing apple juice, for consumption alongside a low catechin diet tailored to participants calorie needs for weight maintenance.
Placebo Comparator: Low catechin
A 3-day controlled diet
Other: Dietary intervention - low catechin diet
The intervention will provide a nutritionally-matched beverage without catechins, for consumption alongside a low catechin diet tailored to participants calorie needs for weight maintenance.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Mean sum catechin metabolites
Time Frame: Post 3-day intervention vs. post 3-day control
Mean difference in sum catechin metabolite concentration in response to the intervention, stratified by ODMA producers and non-producers.
Post 3-day intervention vs. post 3-day control

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Mean individual catechin metabolites
Time Frame: Post 3-day intervention vs. post 3-day control
Mean differences in individual valerolactone and valeric acid concentrations in response to the intervention, stratified by ODMA producers and non-producers.
Post 3-day intervention vs. post 3-day control
Differences in microbiome profiles
Time Frame: Post 3-day intervention vs. post 3-day control
Differences in microbiome profiles in response to the 3-day intervention.
Post 3-day intervention vs. post 3-day control
Difference in microbiome diversity
Time Frame: Post 3-day intervention vs. post 3-day control
Differences in microbiome diversity in response to the 3-day intervention.
Post 3-day intervention vs. post 3-day control
Difference in microbial species abundance
Time Frame: Post 3-day intervention vs. post 3-day control
Differences in microbial species abundance in response to the 3-day intervention.
Post 3-day intervention vs. post 3-day control

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Maryland, College Park

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
MaineHealth
University of Hawaii Cancer Research Center

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Margaret Slavin, PhD, University of Maryland, College Park

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
December 7, 2023

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
May 8, 2025

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
May 8, 2025

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
October 24, 2023

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 24, 2023

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
October 30, 2023

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
June 22, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
June 17, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
June 1, 2025

More Information

Terms related to this study

Keywords

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 2023-05787
  • 2022-67017-41032 (Other Grant/Funding Number: U.S. Department of Agriculture)

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings