Effect of a Food Intervention With a Prebiotic Alone or Combined With B-vitamins on Gut Microbiota Diversity, Inflammation and Mental Health Outcomes in Older Adults (GutFood)

May 11, 2026 updated by: Leane Hoey, University of Ulster

'GutFood' - Effect of a Food Intervention With a Prebiotic Alone or Combined With B-vitamins on Gut Microbiota Diversity, Inflammation and Mental Health Outcomes in Older Adults

Ageing is associated with changes in gut microbiota composition, increased inflammation, and a greater risk of poor mental health outcomes. Nutritional inadequacies, including low dietary fibre intake and suboptimal B-vitamin status, are common in older adults and may contribute to these age-related health issues. Research suggests that increasing dietary fibre intake, particularly through prebiotics such as inulin, may help to improve gut health. In addition, B-vitamins have been linked to both gut and mental health, although their combined effects with prebiotics are not well understood.

With the assistance of a food company, the investigators have developed a functional drink enriched with chicory inulin, alone or in combination with B-vitamins. Therefore, the investigators plan to conduct a 12-week randomised, double-blind, placebo-controlled trial to test the effect of this functional drink on gut health outcomes, nutritional status, inflammation, and mental health in adults aged 50 years and older.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

84

Phase

  • 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 Locations

  • United Kingdom
    • County Londonderry
      • Coleraine, County Londonderry, United Kingdom, BT521SA
        • Recruiting
        • Human Intervention Studies Unit
        • Contact:

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

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Community-dwelling
  • Non or low consumers (≤ 4 portions/week) of foods/beverages fortified with B-vitamins
  • Individuals with the capacity to provide informed consent

Exclusion Criteria:

  • B12 injection users
  • Using supplements containing the nutrients of interest (B-vitamins, inulin, probiotics)
  • Taking medications that interfere with B-vitamin metabolism
  • Currently taking antibiotics
  • GI disease (Crohn's, coeliac)
  • Serious chronic disease (e.g. cancer, liver disease)

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: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Placebo Comparator: Placebo
Dietary supplement: Placebo
A control/placebo drink with similar energy content (~182 kJ / 43 kcal/ per serving) but without the additional nutrient provision.
Active Comparator: Inulin and B-vitamins
Dietary supplement: Inulin and B-vitamins
A functional beverage containing inulin (7.5 g per serving) combined with B-vitamins folic acid (100μg), vitamin B12 (5μg), vitamin B6 (5mg) and riboflavin (2.5mg).
Active Comparator: Inulin only
Dietary supplement: Inulin
A functional drink containing inulin (7.5 g per serving) without additional B-vitamins.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Gut microbiome profile
Time Frame: 12 weeks
Faecal samples will be collected to examine the gut microbiome profile using faecal 16S rRNA profiling, V3-V4 region and QIIME2 pipeline.
12 weeks
Vitamin B12
Time Frame: 12 weeks
Serum total vitamin B12 measured by microbiological assay based on a colistin sulphate-resistant strain of Lactobacillus leichmannii; serum methylmalonic acid measured by gas chromatography-tandem mass spectrometry based on methylchloroformate derivatisation.
12 weeks
Folate
Time Frame: 12 weeks
Serum folate and red blood cell folate measured by microbiological assay based on a chloramphenicol-resistant strain of Lactobacillus casei.
12 weeks
Vitamin B6
Time Frame: 12 weeks
Vitamin B6 status as measured by plasma pyridoxal-5-phosphate using high-performance liquid chromatography with fluorescence detection.
12 weeks
Riboflavin
Time Frame: 12 weeks
Measured using the functional assay erythrocyte glutathione reductase activation coefficient, EGRac
12 weeks
Serum total homocysteine
Time Frame: 12 weeks
Measured by gas chromatography-tandem mass spectrometry based on methylchloroformate derivatisation.
12 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Inflammation
Time Frame: 12 weeks
Markers of inflammation (analysed by enzyme-linked immunosorbent assay): C-reactive protein (CRP), interleukin 6 (IL-6), interleukin 10 (IL-10), tumour necrosis factor (TNF-α).
12 weeks
Gut microbial metabolites
Time Frame: 12 weeks
Faecal short-chain fatty acids (SCFAs)
12 weeks
Depressive symptoms
Time Frame: 12 weeks
Measured using the Centre for Epidemiological Studies Depression Scale (CES-D).
12 weeks
Anxiety symptoms
Time Frame: 12 weeks
Measured using the Hospital Anxiety and Depression Scale (HADS).
12 weeks
Sleep quality
Time Frame: 12 weeks
Measured using the Pittsburgh Sleep Quality Index (PSQI).
12 weeks
Physiological stress
Time Frame: 12 weeks
Serum cortisol concentrations measured as a biomarker of physiological stress.
12 weeks

Collaborators and Investigators

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

Sponsor

University of Ulster

Collaborators

University of Leeds
ABC Nutritionals
Sensus B.V. (Royal Cosun), Roosendaal, The Netherlands

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 (Estimated)

May 18, 2026

Primary Completion (Estimated)

December 1, 2026

Study Completion (Estimated)

December 1, 2026

Study Registration Dates

First Submitted

May 11, 2026

First Submitted That Met QC Criteria

May 11, 2026

First Posted (Actual)

May 18, 2026

Study Record Updates

Last Update Posted (Actual)

May 18, 2026

Last Update Submitted That Met QC Criteria

May 11, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • REC/24/0064

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

All IPD that underlie results in a publication

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.

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