Effects of a diverse prebiotic fibre blend on inflammation, the gut microbiota, and affective symptoms: A pilot open label randomised controlled trial

Emerging evidence suggests that low-grade systemic inflammation plays a key role in altering brain activity, behaviour, and affect. Modulation of the gut microbiota using prebiotic fibre offers a potential therapeutic tool to regulate inflammation, mediated via the production of short-chain fatty acids (SCFAs). However, the impact of prebiotic consumption on affective symptoms, and the possible contribution from inflammation, gut symptoms, and the gut microbiome, is currently underexamined. In this 12-week study, the effects of a diverse prebiotic blend on inflammation, gut microbiota profiles, and affective symptoms in a population with Metabolic Syndrome (MetS) was examined. Sixty patients meeting the criteria for MetS were randomised into a treatment group (n = 40), receiving 10g per day of a diverse prebiotic blend and healthy eating advice and a control group (n = 20), receiving healthy eating advice only. Our results showed a significant reduction in C-reactive protein (CRP), alongside improvements in self-reported affective scores in the treatment compared to the control group. While there were no differences in relative abundance between groups at week 12, there was a significant increase from baseline to week 12 in Bifidobacterium and Parabacteroides in the treatment group, both of which are recognised as SCFA producers. Multivariate regression analyses further revealed that changes in affective scores were positively associated with both gastrointestinal symptoms and CRP. Together, this study provides preliminary support for the use of a diverse prebiotic blend for mood, stress, and anxiety. ### Competing Interest Statement C.V Hall and T. Gurry are employees/shareholders of Myota GmbH. P. Hepsomali has received research funding, consultancy, travel support, and speaking honoraria from various companies. ### Clinical Trial NCT06216626 ### Funding Statement This project was sponsored and funded by Myota GmbH. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The study was approved by the NHS Human Research Ethics Committee of City and East (reference: 23/LO/0515). The study was registered on ClinicalTrials.gov (registration number: [NCT06216626][1]). Written informed consent was obtained for all participants in accordance with the Declaration of Helsinki. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors. [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT06216626&atom=%2Fmedrxiv%2Fearly%2F2024%2F02%2F13%2F2024.02.12.24302681.atom