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Feeding gut microbes to nourish the brain: unravelling the diet–microbiota–gut–brain axis

Nature Metabolism volume 6, pages 1454–1478 (2024)Cite this article

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Abstract

The prevalence of brain disorders, including stress-related neuropsychiatric disorders and conditions with cognitive dysfunction, is rising. Poor dietary habits contribute substantially to this accelerating trend. Conversely, healthy dietary intake supports mood and cognitive performance. Recently, the communication between the microorganisms within the gastrointestinal tract and the brain along the gut–brain axis has gained prominence as a potential tractable target to modulate brain health. The composition and function of the gut microbiota is robustly influenced by dietary factors to alter gut–brain signalling. To reflect this interconnection between diet, gut microbiota and brain functioning, we propose that a diet–microbiota–gut–brain axis exists that underpins health and well-being. In this Review, we provide a comprehensive overview of the interplay between diet and gut microbiota composition and function and the implications for cognition and emotional functioning. Important diet-induced effects on the gut microbiota for the development, prevention and maintenance of neuropsychiatric disorders are described. The diet–microbiota–gut–brain axis represents an uncharted frontier for brain health diagnostics and therapeutics across the lifespan.

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Fig. 1: Lifespan nutrition.
Fig. 2: Implications for neuropsychiatric disorders.
Fig. 3: Mechanisms of action.
Fig. 4: Investigating the diet–microbiota–gut–brain axis.
Fig. 5: Gut microbiota as a potential mediator/moderator.

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Authors and Affiliations

  1. APC Microbiome Ireland, University College Cork, Cork, Ireland

    Elizabeth Schneider, Kenneth J. O’Riordan, Gerard Clarke & John F. Cryan

  2. Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland

    Gerard Clarke

  3. Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland

    John F. Cryan

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E.S., G.C. and J.F.C. conceptualized the article. E.S. and K.J.O. drafted the manuscript. All authors contributed to interpretation, editing and finalization of the manuscript.

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Correspondence to John F. Cryan.

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Competing interests

E.S. has received an honorarium from Janssen Sciences Ireland UC as an invited speaker. K.J.O. has received honoraria from Sanofi Genzyme and Danone. G.C. has received honoraria from Janssen, Probi and Apsen as an invited speaker, is in receipt of research funding from Pharmavite, Reckitt, Tate and Lyle, Nestle and Fonterra, and has received payments as a consultant from Yakult, Zentiva and Heel Pharmaceuticals. J.F.C. has received research funding from IFF, Nutricia and Kerry Foods and has been an invited speaker at meetings organized by Bromotech & Nestle.

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Schneider, E., O’Riordan, K.J., Clarke, G. et al. Feeding gut microbes to nourish the brain: unravelling the diet–microbiota–gut–brain axis. Nat Metab 6, 1454–1478 (2024). https://doi.org/10.1038/s42255-024-01108-6

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