Exploring how gut bacteria affect brain function and behavior through GABA

Mapping the Impact of Gut Bacteria on Brain and Behaviour Through the Lens of GABA (GutBrainGABA)

Not applicable Interventional University of Reading · NCT05698862

This study is testing if a probiotic that helps produce GABA can improve brain function and behavior in people by comparing it to a placebo over 12 weeks.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment60 (estimated)
Ages18 Years to 50 Years
SexMale
SponsorUniversity of Reading Academic / other
Locations1 site (Reading)
Trial IDNCT05698862 on ClinicalTrials.gov

What this trial studies

This interventional trial investigates the relationship between gut microbiota and brain function, focusing on the neurotransmitter GABA. Participants will undergo a double-blind, placebo-controlled crossover design over 12 weeks, involving both a probiotic supplement and a placebo. The study will assess changes in behavior and brain activity through various measures, including fecal, blood, and urine samples. The probiotic used is Lactobacillus brevis, known for its GABA production capabilities, and participants will be required to maintain a food diary and adhere to supplement intake.

Who should consider this trial

Good fit: Ideal candidates are healthy, right-handed, Caucasian males aged 18 to 50 with a BMI between 18.5 and 30 who have lived in the UK or Europe.

Not a fit: Patients with neurological, developmental, or psychiatric conditions, or those with gut-related disorders, will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could enhance our understanding of how gut health influences mental well-being and behavior.

How similar studies have performed: While some studies have explored gut microbiota's impact on mental health, this specific approach focusing on GABA is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Male
* Right-handed
* Caucasian/White
* Between 18 and 50 years of age
* Grew up in the UK or other European country
* Body Mass Index 18.5 to 30.

Exclusion Criteria:

* Use of antibiotics within the last 3 months
* Use of protonic pump inhibitors (PPIs) within the last 3 months
* Current or history of regular smoking within the last 6 months
* Regular consumption of \>14 units of alcohol per week
* Current use of psychotropic drugs for medicinal or recreational purposes
* Current use of probiotic/prebiotic supplements
* Current diagnosis of neurological, developmental or psychiatric condition
* Current diagnosis of gut microbiota related conditions such as inflammatory bowel disease or irritable bowel syndrome

Where this trial is running

Reading

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions HealthyGamma Amino Butyric AcidBrain functionGut microbiotaBehaviourProbiotics
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.