The Impact of Food on Gut Microbiome Composition - a Clinical Trial Determining the Influence of Diet in Gut Microbiome Colonisation and Host Health

NCT ID: NCT05986955

Last Updated: 2025-04-24

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: EARLY_PHASE1
• Total Enrollment: 25 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2023-06-16
• Study Completion Date: 2023-11-28

Brief Summary

The goal of this clinical trial is to examine the impact of food derived bacteria on gut microbiome composition and host health. The main questions it aims to answer are:

• what is the the rate of gastrointestinal colonisation of food derived bacteria?
• what is the contribution of food derived bacteria to gut microbiome stability?

Participants will complete a cross over feeding study of dietitian designed meals of known microbial load and will be asked to provide stool and blood samples for analysis.

Detailed Description

To understand the role and stability of food derived bacteria in impacting microbiome composition, 20 healthy participants will be recruited for this single site double blinded randomised controlled crossover pilot trial. The study is divided into four 14 day diet phases - baseline habitual, specified diet 1, habitual washout and specified diet 2. Participants will be randomly assigned to receive a microbial or non-microbial diet in specified diet 1 phase. Each participant will then crossover to receive the alternative diet in the specified diet 2 phase. The microbial and non-microbial diets will be identical except for the removal of naturally occurring food derived bacteria in non-microbial diet. At the commencement of the study and at the end of each diet phase, participants will attend a research clinic to undergo comprehensive clinical and anthropometric assessment and dietary evaluation.

Conditions

Healthy

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: OTHER
• Blinding Strategy: QUADRUPLE

Study Groups

Specified Diet 1 - Microbial Diet

Participants provided with a typical Australian diet including all food groups as described by the Australian Guide to Healthy Eating without any dietary exclusions. Meals have been designed by researchers and dietitians and prepared by professional chefs.

Group Type: EXPERIMENTAL

Diet

Intervention Type: OTHER

Participants will be assigned prospectively to microbial or non-microbial diet for first phase of trial and will then cross over to the alternate diet following a washout period.

Specified Diet 2 - Non-microbial Diet

Diet provided to participants is identical to Specified Diet 1 however after cooking and packaging, food for this arm will be sterilised by irradiation in line with International Organisation for Standardisation (ISO) standards and Australian code of good manufacturing practice.

Group Type: ACTIVE_COMPARATOR

Diet

Intervention Type: OTHER

Participants will be assigned prospectively to microbial or non-microbial diet for first phase of trial and will then cross over to the alternate diet following a washout period.

Interventions

Diet

Participants will be assigned prospectively to microbial or non-microbial diet for first phase of trial and will then cross over to the alternate diet following a washout period.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Have no genetic conditions (e.g. Prader Willi or Down's Syndrome)
• Not diagnosed with a significant medical conditions (e.g. irritable bowel syndrome, inflammatory bowel disease or type 1/2 diabetes)
• Do not require drug-therapy (e.g. steroids or insulin or antibiotics)
• Not taking dietary supplements, probiotics, prebiotics, symbiotics or fibre supplementation
• Any condition that will affect participation in the study
• Not pregnant, planning a pregnancy or breastfeeding
• Able to complete a two-month dietary study and agree to eating all meals provided
• Have no dietary allergies or dietary restrictions that prevent consumption of provided study meals
• Open bowels regularly - mostly daily
• Able to read, write and understand English

Exclusion Criteria

• Dietary concerns identified by dietitian
• Aged less than 18 years and older than 65 years
• Diagnosed with a medical condition that requires drug therapy
• Taking medications or supplements known to alter gastrointestinal microbiota
• Women who are pregnant, planning a pregnancy or breastfeeding
• Anyone with a diagnosed gastrointestinal condition/disease e.g. irritable bowel syndrome or inflammatory bowel disease
• Known dietary allergy and/or intolerance, follows a vegan or vegetarian diet, or has coeliac disease
• Anyone with a preference for specific food avoidance or exclusion of certain ingredients in habitual diet
• Unable to tolerate blood collection procedures
• Unable to provide regular stool samples throughout the study

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Monash University

OTHER

Sponsor Role: lead

Responsible Party

Dr. Sam Forster

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Dr. Sam Forster

Role: PRINCIPAL_INVESTIGATOR

Hudson Institue, Monash University

Locations

BASE Facility

Notting Hill, Victoria, Australia

Countries

Australia

Other Identifiers

RES-21-0000-602A

Identifier Type: -

Identifier Source: org_study_id