Gut Microbial Metabolites of Apple Polyphenols

NCT06107192 | Completed

• 2 other identifiers: 2023-057872022-67017-41032
• Study Type: interventional
• Target: 32
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Healthy; Controlled Feeding Trial

Keywords

Gut microbiome; Flavonoids; Isoflavones; Catechin

Outcome Measures

Primary Outcomes (1)

• Mean sum catechin metabolites

  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 Outcomes (4)

• Mean individual catechin metabolites

  Post 3-day intervention vs. post 3-day control

• Differences in microbiome profiles

  Post 3-day intervention vs. post 3-day control

• Difference in microbiome diversity

  Post 3-day intervention vs. post 3-day control

• Difference in microbial species abundance

  Post 3-day intervention vs. post 3-day control

Study Arms (2)

Apple catechin

EXPERIMENTAL

A 3-day controlled diet

Other: Dietary intervention - apple catechin diet

Low catechin

PLACEBO COMPARATOR

A 3-day controlled diet

Other: Dietary intervention - low catechin diet

Interventions

Dietary intervention - apple catechin diet OTHER

The intervention will provide a catechin-containing apple juice, for consumption alongside a low catechin diet tailored to participants calorie needs for weight maintenance.

Apple catechin

Dietary intervention - low catechin diet OTHER

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.

Low catechin

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Completion of informed consent.
• Stated willingness to comply with all study procedures and availability for the duration of the study.
• Any gender identification, aged 18 - 45.
• BMI 18.5 - 40 kg/m\^2
• Ability to consume the intervention foods and beverages and be willing to adhere to the dietary regimen.
• Agreement to provide urine and fecal samples according to the study protocol.
• Agreement to adhere to avoid high catechin foods (tea, chocolate) for 4 weeks.
• Able to come to the study location for 8 visits according to the study schedule.
• 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.

You may not qualify if:

• Current, regular use of antacids or acid reducers.
• Systemic antibiotic use within the past month prior to the urinary screening until completion of the dietary intervention.
• Pregnancy or lactation, within 3 months post-partum (regardless of breastfeeding) at screening or planning to become pregnant during the study duration.
• 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.
• Current diagnosis of renal, hepatic, or gastrointestinal conditions.
• History of stroke.
• Underweight (BMI \<18.5 kg/m\^2) or severe obesity (BMI \>40 kg/m\^2).
• Under 18 years or above 45 years of age.
• Unwilling or unable to participate in the controlled dietary intervention or provide urine or fecal samples.
• Has a pacemaker, implanted defibrillator, or other implanted electronic device.
• Change of body weight \>10% between screening and dietary intervention.

Sponsors & Collaborators

• University of Maryland, College Park: lead
• MaineHealth: collaborator
• University of Hawaii Cancer Research Center: collaborator

Study Sites (1)

Department of Nutrition and Food Science

College Park, Maryland, 20742, United States

Location

Study Officials

• Margaret Slavin, PhD

  University of Maryland, College Park

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: During the crossover trial of two diets, participants will receive the same foods during both arms. The intervention and control will be delivered by a beverage containing either the active component or a nutritionally equivalent control beverage with similar flavor. Participants will not be told the order of study arms they receive. Drinks will be labeled with a code by a different researcher than the team interacting with participants. The statistician will not know which code corresponds to which intervention until analysis is complete.
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 24, 2023
• First Posted: October 30, 2023
• Study Start: December 7, 2023
• Primary Completion: May 8, 2025
• Study Completion: May 8, 2025
• Last Updated: June 22, 2025

Record last verified: 2025-06

Locations

US (1)