Prebiotics, probiotics, fermented foods and cognitive outcomes: A meta-analysis of randomized controlled trials

Wolfgang Marx; Andrew Scholey; Joseph Firth; Nathan M D'Cunha; Melissa Lane; Meghan Hockey; Melanie M Ashton; John F Cryan; Adrienne O'Neil; Nenad Naumovski; Michael Berk; Olivia M Dean; Felice Jacka

doi:10.1016/j.neubiorev.2020.07.036

Prebiotics, probiotics, fermented foods and cognitive outcomes: A meta-analysis of randomized controlled trials

Neurosci Biobehav Rev. 2020 Nov:118:472-484. doi: 10.1016/j.neubiorev.2020.07.036. Epub 2020 Aug 27.

Authors

Wolfgang Marx¹, Andrew Scholey², Joseph Firth³, Nathan M D'Cunha⁴, Melissa Lane⁵, Meghan Hockey⁵, Melanie M Ashton⁵, John F Cryan⁶, Adrienne O'Neil⁷, Nenad Naumovski⁴, Michael Berk⁸, Olivia M Dean⁵, Felice Jacka⁵

Affiliations

¹ Deakin University, iMPACT, School of Medicine, Geelong, Australia. Electronic address: wolf.marx@deakin.edu.au.
² Centre for Human Psychopharmacology, Swinburne University, VIC 3122, Australia.
³ NICM Health Research Institute, Western Sydney University, Westmead, Australia; Division of Psychology and Mental Health, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
⁴ Faculty of Health, University of Canberra, Bruce, ACT 2601, Australia.
⁵ Deakin University, iMPACT, School of Medicine, Geelong, Australia.
⁶ APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland.
⁷ Deakin University, iMPACT, School of Medicine, Geelong, Australia; Melbourne School of Population and Global Health, University of Melbourne, Australia.
⁸ Deakin University, iMPACT, School of Medicine, Geelong, Australia; Orygen, The National Centre of Excellence in Youth Mental Health, Centre for Youth Mental Health, Florey Institute for Neuroscience and Mental Health and the Department of Psychiatry, The University of Melbourne, Melbourne, Australia.

PMID: 32860802
DOI: 10.1016/j.neubiorev.2020.07.036

Abstract

This systematic review and meta-analysis aimed to evaluate randomized controlled trials that investigated the use of probiotic, prebiotic, and fermented food interventions for cognitive performance. In total, 22 studies (n = 1551) were included that investigated probiotics (11 studies, n = 724), prebiotics (5 studies, n = 355), and fermented foods (6 studies, n = 472). Despite several individual studies (14 of 22) reporting significant improvements in specific cognitive domains, results of the pooled meta-analysis found no significant effect for any intervention for global cognition (Probiotics: g = 0.115, 95 %CI -0.041, 0.270, p = 0.148; Prebiotics: g = 0.077, 95 %CI -0.091, 0.246, p = 0.369; Fermented food: g = 0.164 95 %CI -0.017, 0.345, p = 0.076) or any individual cognitive domain. Most studies (16 of 22) had low risk of bias. These results do not support the use of probiotic, prebiotic, and fermented food interventions for cognitive outcomes. This may be due to the limited number of small and short-term studies as well clinical heterogeneity relating to the population, cognitive tests, and intervention. Therefore, further trials that investigate these interventions in clinical populations using adequately powered samples are warranted. PROSPERO: CRD42019137936.

Keywords: Cognition; Fermented foods; Meta-analysis; Prebiotic; Probiotic.

Publication types

Meta-Analysis
Research Support, Non-U.S. Gov't
Review
Systematic Review

MeSH terms

Cognition
Fermented Foods*
Humans
Prebiotics
Probiotics*
Randomized Controlled Trials as Topic

Substances

Prebiotics

Grants and funding

MR/T021780/1/MRC_/Medical Research Council/United Kingdom