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Cited by 193Gut microbiota and healthNutritional Studies and DietGastrointestinal motility and disorders

Role of diet and its effects on the gut microbiome in the pathophysiology of mental disorders

Open access
Horn, J., Mayer, D. E., Chen, S., Mayer, E. A.·2022·Translational Psychiatry
DOI 10.1038/s41398-022-01922-0PMC PMC9021202
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Abstract

There is emerging evidence that diet has a major modulatory influence on brain-gut-microbiome (BGM) interactions with important implications for brain health, and for several brain disorders. The BGM system is made up of neuroendocrine, neural, and immune communication channels which establish a network of bidirectional interactions between the brain, the gut and its microbiome. Diet not only plays a crucial role in shaping the gut microbiome, but it can modulate structure and function of the brain through these communication channels. In this review, we summarize the evidence available from preclinical and clinical studies on the influence of dietary habits and interventions on a selected group of psychiatric and neurologic disorders including depression, cognitive decline, Parkinson’s disease, autism spectrum disorder and epilepsy. We will particularly address the role of diet-induced microbiome changes which have been implicated in these effects, and some of which are shared between different brain disorders. While the majority of these findings have been demonstrated in preclinical and in cross-sectional, epidemiological studies, to date there is insufficient evidence from mechanistic human studies to make conclusions about causality between a specific diet and microbially mediated brain function. Many of the dietary benefits on microbiome and brain health have been attributed to anti-inflammatory effects mediated by the microbial metabolites of dietary fiber and polyphenols. The new attention given to dietary factors in brain disorders has the potential to improve treatment outcomes with currently available pharmacological and non-pharmacological therapies.

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Written from the paper’s full text.

TL;DR

This narrative review argues that diet shapes the gut microbiome and brain-gut-microbiome (BGM) signaling, with anti-inflammatory microbial metabolites of fiber and polyphenols implicated in several psychiatric and neurologic disorders. It concludes that evidence is mostly preclinical or cross-sectional and that causal, mechanistic human data remain insufficient.

Key findings

  • BGM communication occurs through neuroendocrine, neural, and immune channels; 95% of the body’s serotonin is produced and stored in enterochromaffin cells, germ-free mice have half the serotonin of mice with a normal microbiome, and SCFAs/butyrate exert anti-inflammatory effects via GPR43/IL-10 and can reverse microglia impairments.
  • In depression, the 12-week SMILES RCT in 33 participants with moderate-to-severe depression found a statistically significant decrease in depression symptoms with dietary support versus social support; PREDIMED (7,447 adults aged 55–80 over 8 years) found average depression risk 20% lower in the intervention group (not statistically significant) and 40% lower in the type-2 diabetes subset (significant). For anxiety, a meta-analysis of 11 RCTs in 2,270 individuals found no overall effect (g = 0.100, 95% CI = −0.036 to 0.235, p = .148), but studies with >75% female participants showed positive effects (g = 0.211, p = 0.001).
  • In cognitive decline/AD/PD, the 1-year NUAGE trial in 612 participants across 5 European countries found Mediterranean-diet adherence correlated with butyrate-producing taxa negatively associated with inflammatory markers and positively associated with low frailty; early clinical studies report ketogenic diets improve cognition in AD/MCI; and the MIND diet in 706 participants aged 59–97 was associated with lower parkinsonism risk and slower PD symptom progression.
  • In ASD and epilepsy, microbiota transfer therapy produced sustained decreases in GI and ASD symptoms and favorable changes in Bifidobacteria, Prevotella, and Desulfovibrio; an open-label gluten-free/casein-free diet in 70 children improved 81% after 3 months; a meta-analysis of 10 RCTs found weak positive seizure reduction with ketogenic diets; and one-week ketogenic diet in 14 children with drug-resistant epilepsy versus 30 controls produced 50% seizure reduction in infants, with decreased Cronobacter and increased Bifidobacterium, Bacteroides, and Prevotella.

Methods

  • Design: narrative review of preclinical and clinical literature on diet, the gut microbiome, and BGM interactions in selected psychiatric and neurologic disorders, including depression, cognitive decline/AD, Parkinson’s disease, ASD, and epilepsy; Table 1 also covers anxiety, eating disorders, and ADHD.
  • Data/sample: no primary sample; synthesizes animal studies, cross-sectional/epidemiological studies, RCTs, meta-analyses, and small clinical trials, with examples including SMILES (n = 33), PREDIMED (n = 7,447), NUAGE (n = 612), MIND (n = 706), microbiota transfer therapy in ASD, and ketogenic diet studies in epilepsy.
  • Main analysis: narrative synthesis organized by BGM communication channels and by disorder, with summary tables of evidence and challenges; no systematic search strategy or quantitative pooling is reported.

Limitations

  • Stated: the majority of findings come from preclinical and cross-sectional epidemiological studies; there is insufficient evidence from mechanistic human studies to conclude causality between a specific diet and microbially mediated brain function; high-quality RCTs are scarce; dietary assessment relies on questionnaires/interviews that are unreliable; long-term standardized diet implementation and adherence are challenging; translatability from animal models is poor; and disease specificity of altered microbial signaling remains unresolved.
  • Stated: many ASD dietary intervention studies are small, low quality, and lack blinding/randomization; ketogenic diet evidence in epilepsy is mixed and limited by attrition and short follow-up; fecal microbiota transplant evidence is inconsistent except for an uncontrolled ASD study.
  • Evident from the text: as a narrative review, it does not report a systematic search strategy, inclusion criteria, risk-of-bias assessment, or meta-analysis, and the authors explicitly describe the disorder selection as limited and non-exhaustive.

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Registry

Crossref · 10.1038/s41398-022-01922-0

Cites

Statistics

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Claims the paper makes

0 of 145 cited sources checked · 0 supported · 0 flagged

  • Interpretationreasoning

    There is insufficient evidence from mechanistic human studies to make conclusions about causality between a specific diet and microbially mediated brain function.

    “to date there is insufficient evidence from mechanistic human studies to make conclusions about causality between a specific diet and microbially mediated brain function.”
    Quote in the paperSubstantial claim
  • Premisecitation

    Gut microbes communicate with a variety of cells of the gastrointestinal endocrine system.

    “Gut microbes communicate with a variety of cells of the gastrointestinal endocrine system [22].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [22] Furness JB. The enteric nervous system and neurogastroenterology. Nat Rev Gastroenterol Hepatol. 2012;9:286–94. source

      Not checked in the free run.

  • Premisecitation

    Enteroendocrine and enterochromaffin cells form close synaptic connections with certain vagal afferent fibers through neuropods.

    “Enteroendocrine and enterochromaffin cells (ECCs) form close synaptic connections with certain vagal afferent fibers through cell extensions called neuropods [25, 26].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [25] Kaelberer MM, Rupprecht LE, Liu WW, Weng P, Bohórquez DV. Neuropod cells: the emerging biology of gut-brain sensory transduction. Annu Rev Neurosci. 2020;43:337–53. source

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    • cites [26] Bohórquez DV, Shahid RA, Erdmann A, Kreger AM, Wang Y, Calakos N. et al. Neuroepithelial circuit formed by innervation of sensory enteroendocrine cells. J Clin Invest. 2015;125:782–6. source

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  • Premisecitation

    Direct modulation of gut microbial gene expression and function by norepinephrine and likely other neurotransmitters released from postsynaptic sympathetic terminals has been reported.

    “In addition, direct modulation of gut microbial gene expression and function by norepinephrine and likely other neurotransmitters released from postsynaptic sympathetic terminals has been reported [18].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [18] Martin CR, Osadchiy V, Kalani A, Mayer EA. The brain-gut-microbiome axis. Cell Mol Gastroenterol Hepatol. 2018;6:133–48. source

      Not checked in the free run.

  • Premisereasoning

    The health benefit of non-absorbable dietary components is crucially dependent on the composition and functions of the gut microbiome.

    “The health benefit of these non-absorbable dietary components is crucially dependent on the composition and functions of the gut microbiome.”
    Quote in the paperSubstantial claim
  • May combine two claims. 47
  • Classified as probably not a substantial claim. 10

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    Premisecitation

    Large epidemiological studies have implicated dietary factors in some psychiatric disorders as risk factors and potential therapies.

    “a number of large epidemiological studies have implicated dietary factors in some of these disorders [1–5], both in terms of risk factors [6] as well as potential therapies [2, 5, 7].”
    Quote in the paperSubstantial claim0 of 7 sources checked
    • cites [1] Parletta N, Zarnowiecki D, Cho J, Wilson A, Bogomolova S, Villani A. et al. A Mediterranean-style dietary intervention supplemented with fish oil improves diet quality and mental health in people with depression: a randomized controlled trial (HELFIMED). Nutr Neurosci. 2019;22:474–87. source

      Not checked in the free run.

    • cites [2] Jacka FN, O’Neil A, Opie R, Itsiopoulos C, Cotton S, Mohebbi M. et al. A randomised controlled trial of dietary improvement for adults with major depression (the ‘SMILES’ trial) [published correction appears in BMC Med. 2018 Dec 28;16(1):236]. BMC Med. 2017;15:23. source

      Not checked in the free run.

    • cites [3] Sánchez-Villegas A, Martínez-González MA, Estruch R, Salas-Salvadó J, Corella D, Covas MI. et al. Mediterranean dietary pattern and depression: the PREDIMED randomized trial. BMC Med. 2013;11:208. source

      Not checked in the free run.

    • cites [4] Ota M, Matsuo J, Ishida I, Takano H, Yokoi Y, Hori H. et al. Effects of a medium-chain triglyceride based ketogenic formula on cognitive function in patients with mild-to-moderate Alzheimer’s disease. Neurosci Lett. 2019;690:232–6. source

      Not checked in the free run.

    • cites [5] Ghalichi F, Ghaemmaghami J, Malek A, Ostadrahimi A. Effect of gluten free diet on gastrointestinal and behavioral indices for children with autism spectrum disorders: a randomized clinical trial. World J Pediatr. 2016;12:436–42. source

      Not checked in the free run.

    • cites [6] Ghosh TS, Rampelli S, Jeffery IB, Santoro A, Neto M, Capri M. et al. Mediterranean diet intervention alters the gut microbiome in older people reducing frailty and improving health status: the NU-AGE 1-year dietary intervention across five European countries. Gut. 2020;69:1218–28. source

      Not checked in the free run.

    • cites [7] Adams JB, Audhya T, Geis E, Gehn E, Fimbres V, Pollard EL. et al. Comprehensive nutritional and dietary intervention for autism spectrum disorder-a randomized, controlled 12-month trial. Nutrients. 2018;10:369. source

      Not checked in the free run.

  • May combine two claims.

    Premisereasoning

    Diet plays a crucial role in shaping the gut microbiome and can modulate brain structure and function through BGM communication channels.

    “Diet not only plays a crucial role in shaping the gut microbiome, but it can modulate structure and function of the brain through these communication channels.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisereasoning

    Diet has a major modulatory influence on brain-gut-microbiome interactions, with implications for brain health and several brain disorders.

    “There is emerging evidence that diet has a major modulatory influence on brain-gut-microbiome (BGM) interactions with important implications for brain health, and for several brain disorders.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Premisenone given

    The BGM system is made up of neuroendocrine, neural, and immune communication channels which establish a network of bidirectional interactions between the brain, the gut and its microbiome.

    “The BGM system is made up of neuroendocrine, neural, and immune communication channels which establish a network of bidirectional interactions between the brain, the gut and its microbiome.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Evidence for release of stress-induced serotonin from enterochromaffin cells into the gut lumen has been reported, with some microbes exhibiting a serotonin transporter in their cell membranes.

    “Evidence for a similar release of stress-induced serotonin from enterochromaffin cells into the gut lumen has been reported, with some microbes exhibiting a serotonin transporter in their cell membranes [19].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [19] Yano JM, Yu K, Donaldson GP, Shastri GG, Ann P, Ma L. et al. Indigenous bacteria from the gut microbiota regulate host serotonin biosynthesis [published correction appears in Cell. 2015 Sep 24;163:258]. Cell. 2015;161:264–76. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Converging results from studies support a potential role of diet and a possible beneficial role of particular dietary interventions in different brain disorders including depression, cognitive decline, AD, ASD, and certain forms of epilepsy.

    “Converging results from these studies support a potential role of diet, and a possible beneficial role of particular dietary interventions in different brain disorders, including, but not limited to depression, cognitive decline, and Alzheimer’s disease (AD), ASD, and certain forms of epilepsy”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Premisenone given

    A growing number of interventional and mechanistic studies have confirmed a beneficial effect of a mostly plant-based diet, high in fiber and polyphenols, on mental health.

    “A growing number of interventional and mechanistic studies have confirmed a beneficial effect of a mostly plant-based diet, high in fiber and polyphenols, on mental health.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Interaction of such hormones in the periphery and hypothalamus plays a key role in regulation of appetite and satiety, and dysregulation has been implicated in obesity and food addiction.

    “The interaction of such hormones in the periphery and in the hypothalamus play a key role in the regulation of appetite and satiety [23] and a dysregulation of these signaling systems has been implicated in obesity and food addiction [24].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [23] Burger KS, Berner LA. A functional neuroimaging review of obesity, appetitive hormones and ingestive behavior. Physiol Behav. 2014;136:121–7. source

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    • cites [24] Frank J, Gupta A, Osadchiy V, Mayer EA. Brain-gut-microbiome interactions and intermittent fasting in obesity. Nutrients. 2021;13:584. source

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    Premisecitation

    Kynurenine can pass the blood-brain barrier and has been shown to produce neuroinflammation and neurodegeneration, which have also been reported in AD and depression.

    “Kynurenine, which can pass the blood-brain barrier, has been shown to produce neuroinflammation and neurodegeneration, which have also been reported in AD and depression [31].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [31] Kennedy PJ, Cryan JF, Dinan TG, Clarke G. Kynurenine pathway metabolism and the microbiota-gut-brain axis. Neuropharmacology. 2017;112:399–412. source

      Not checked in the free run.

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    Premisecitation

    Trp metabolites are important contributors to neuroendocrine and neuroimmune mechanisms as they can act on the CNS through the bloodstream or via vagal afferent signaling.

    “Trp metabolites are important contributors to neuroendocrine and neuroimmune mechanisms as they can act on the CNS either through the bloodstream or via vagal afferent signaling [18].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [18] Martin CR, Osadchiy V, Kalani A, Mayer EA. The brain-gut-microbiome axis. Cell Mol Gastroenterol Hepatol. 2018;6:133–48. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The great majority of the body's serotonin (95%) is produced and stored in ECCs and plays an important role in modulating the activity of the enteric nervous system and in signaling to the brain via vagal afferents.

    “The great majority of the body’s serotonin (95%) is produced and stored in ECCs and plays an important role in modulating the activity of the enteric nervous system and in signaling to the brain via different subtypes of vagal afferents which form synaptic contacts with ECCs [29].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [29] Vuong HE, Yano JM, Fung TC, Hsiao EY. The microbiome and host behavior. Annu Rev Neurosci. 2017;40:21–49. source

      Not checked in the free run.

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    Premisecitation

    Higher kynurenine concentrations in the brain were correlated with increased depression-like behavior, which was reduced by administration of Lactobacillus.

    “In these studies, higher kynurenine concentrations in the brain were correlated with increased depression-like behavior which was reduced by the administration of Lactobacillus [30].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [30] Marin IA, Goertz JE, Ren T, Rich SS, Onengut-Gumuscu S, Farber E. et al. Microbiota alteration is associated with the development of stress induced despair behavior. Sci Rep. 2017;7:43859. source

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    Premisecitation

    Indoles are precursor molecules to many compounds critical for brain health and function and have been detected in the GI tract, brain, and systemic circulation.

    “Indoles are precursor molecules to many compounds that are critical for brain health and function and have been detected in the GI tract, brain, and the systemic circulation [32].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [32] Agus A, Planchais J, Sokol H. Gut microbiota regulation of tryptophan metabolism in health and disease. Cell Host Microbe. 2018;23:716–24. source

      Not checked in the free run.

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    Premisecitation

    The gut microbiome can influence central immune activation through direct activation of the gut based immune system and trigger pro- and anti-inflammatory systemic immune responses.

    “The gut microbiome can influence central immune activation through direct activation of the gut based immune system and trigger pro- and anti-inflammatory systemic immune responses [35].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [35] de Lartigue G, Barbier de la Serre C, Espero E, Lee J, Raybould HE. Diet-induced obesity leads to the development of leptin resistance in vagal afferent neurons. Am J Physiol Endocrinol Metab. 2011;301:E187–E195. source

      Not checked in the free run.

  • May combine two claims.

    Premisenone given

    LPS and MAMPs in cell wall of gram-negative microbes can interact locally with TLRs on enteric neurons or vagal afferents, with gut-based immune system, or exert effects distally including brain.

    “Lipopolysaccharides (LPS) and microbe associated molecular patterns (MAMPs) contained in the cell wall of gram-negative microbes can interact locally with receptors on enteric neurons or vagal afferents (so called toll-like receptors or TLRs), with cells of the gut-based immune system, or exert their effects distally throughout the body, including the brain.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Another study with germ-free mice found functional defects in microglia and heightened levels of proinflammatory cytokines IL-1B, IL-6, and TNF-alpha, indicating impairment in immune function.

    “Another study with germ-free mice found functional defects in microglia and as a result observed heightened levels of proinflammatory cytokines IL-1B, IL-6, and TNF-alpha [39], indicating an impairment in immune function.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [39] Matcovitch-Natan O, Winter DR, Giladi A, Vargas Aguilar S, Spinrad A, Sarrazin S. et al. Microglia development follows a stepwise program to regulate brain homeostasis. Science. 2016;353:aad8670 source

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  • May combine two claims.

    Interpretationreasoning

    The close link between inflammatory signals originating in the gut in response to certain diets, in particular the Standard American Diet, and the crucial role of the gut microbiota in generation of both pro- and anti-inflammatory signals emphasize important but incompletely understood interactions between diet, the gut microbiome, and brain diseases.

    “In summary, the close link between inflammatory signals originating in the gut in response to certain diets, in particular the Standard American Diet, and the crucial role of the gut microbiota in the generation of both pro- and anti-inflammatory signals emphasize the important, but incompletely understood interactions between diet, the gut microbiome, and brain diseases.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Metabolic endotoxemia results from a compromised gut barrier, allowing contacts between gut microbial cell wall components and Toll-like receptors on dendritic cells, or after translocation of intact microbes and activation of other cells in the gut-associated immune system.

    “As reviewed elsewhere [12], metabolic endotoxemia results from a compromised gut barrier (“leaky gut”), allowing contacts between gut microbial cell wall components and Toll-like receptors on dendritic cells, or after translocation of intact microbes and activation of other cells in the gut-associated immune system.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [12] Osadchiy V, Martin CR, Mayer EA. Gut microbiome and modulation of CNS function. Compr Physiol. 2019;10:57–72. source

      Not checked in the free run.

  • May combine two claims.

    Premisenone given

    Dysregulation of microglia and gut microbial dysbiosis have been implicated in several psychiatric disorders, such as anxiety, depression, neurodegenerative disorders such as Parkinson's and multiple sclerosis, and neurodevelopmental disorders such as ASD.

    “Dysregulation of microglia and gut microbial dysbiosis have been implicated in several psychiatric disorders, such as anxiety, depression, neurodegenerative disorders, such as Parkinson’s and multiple sclerosis, and neurodevelopmental disorders, such as ASD.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The gut microbiome influences serotonin production and secretion as a direct result of the food we eat (in particular the amount of Trp), as diet modulates microbial composition.

    “The gut microbiome influences serotonin production and secretion as a direct result of the food we eat (in particular the amount of Trp), as diet modulates microbial composition [46].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [46] Singh R, Salem A, Nanavati J, Mullin GE. The role of diet in the treatment of irritable bowel syndrome: a systematic review. Gastroenterol Clin North Am. 2018;47:107–37. source

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  • May combine two claims.

    Premisecitation

    In the CNS, serotonin produced and stored in the raphe nuclei as well as vagal signals generated by release of serotonin from ECCs is crucial to the regulation of sleep, appetite, pain sensitivity and mood.

    “In the CNS, serotonin produced and stored in the raphe nuclei as well as vagal signals generated by release of serotonin from ECCs is crucial to the regulation of sleep, appetite, pain sensitivity and mood [18].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [18] Martin CR, Osadchiy V, Kalani A, Mayer EA. The brain-gut-microbiome axis. Cell Mol Gastroenterol Hepatol. 2018;6:133–48. source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Specific micronutrients such as omega-3 fatty acids and zinc may have an important effect on brain development and function independent of the gut microbiome.

    “Specific micronutrients such as omega-3 fatty acids and zinc may have an important effect on brain development and function independent of the gut microbiome [50].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [50] Sarris J, Murphy J, Mischoulon D, Papakostas GI, Fava M, Berk M. et al. Adjunctive nutraceuticals for depression: a systematic review and meta-analyses. Am J Psychiatry. 2016;173:575–87. source

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    Premisecitation

    Many of these nutrients serve as cofactors for enzymes, supporting synthesis of neurotransmitters, myelination, cell signaling, and metabolic pathways.

    “Many of these nutrients serve as cofactors for enzymes, supporting for example the synthesis of neurotransmitters, myelination, cell signaling, and metabolic pathways [56].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [56] Tardy AL, Pouteau E, Marquez D, Yilmaz C, Scholey A. Vitamins and minerals for energy, fatigue and cognition: a narrative review of the biochemical and clinical evidence. Nutrients. 2020;12:228 source

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    Interpretationcitation

    The nature of dysbiosis in MDD varies across studies, no consistent microbial biomarker has been identified, and causality between gut dysbiosis and clinical symptoms of depression has not been established.

    “although the nature of the dysbiosis in each of the studies varies, has not identified a consistent microbial biomarker, and causality between gut dysbiosis and clinical symptoms of depression has not been established.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [62] Kelly JR, Borre Y, O’ Brien C, Patterson E, El Aidy S, Deane J. et al. Transferring the blues: depression associated gut microbiota induces neurobehavioural changes in the rat. J Psychiatr Res. 2016;82:109–18. source

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    • cites [63] Zheng P, Zeng B, Zhou C, Liu M, Fang Z, Xu X. et al. Gut microbiome remodeling induces depressive like behaviors through a pathway mediated by the host’s metabolism. Mol Psychiatry. 2016;21:786–96. source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Depression prevalence has been increasing, in particular in younger age groups.

    “Depression (major depressive disorder, MDD, or clinical depression) has been increasing in prevalence, in particular in younger age groups [61].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [61] National Institute of Mental Health. (2017). Results from the 2017 National Survey on Drug Use and Health. National Institute of Mental Health. https://www.nimh.nih.gov/health/statistics/major-depression.

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    Premisecitation

    Participants with low relative abundance of Bacteroides showed lower quality of life scores and higher prevalence of depression.

    “The participants with low relative abundance of Bacteroides showed lower quality of life scores and higher prevalence of depression.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [64] Valles-Colomer M, Falony G, Darzi Y, Tigchelaar EF, Wang J, Tito RY. et al. The neuroactive potential of the human gut microbiota in quality of life and depression. Nat Microbiol. 2019;4:623–32. source

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    Premisecitation

    A nutrient-poor diet may lead to nutrient deficiencies, which have been associated with mental health issues.

    “And there is evidence that a nutrient-poor diet may lead to nutrient deficiencies, which have been associated with mental health issues [67, 68].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [67] Jacka FN, Maes M, Pasco JA, Williams LJ, Berk M. Nutrient intakes and the common mental disorders in women. J Affect Disord. 2012;141:79–85. source

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    • cites [68] Jacka FN, Pasco JA, Williams LJ, Meyer BJ, Digger R, Berk M. Dietary intake of fish and PUFA, and clinical depressive and anxiety disorders in women. Br J Nutr. 2013;109:2059–66. source

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    Premisecitation

    Coprococcus and Dialister were positively associated with quality of life and depleted in treatment-free depression.

    “The bacterial taxa Coprococcus and Dialister were found to be positively associated with quality of life and depleted in treatment-free depression.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [64] Valles-Colomer M, Falony G, Darzi Y, Tigchelaar EF, Wang J, Tito RY. et al. The neuroactive potential of the human gut microbiota in quality of life and depression. Nat Microbiol. 2019;4:623–32. source

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  • May combine two claims.

    Study design and conductcitation

    The SMILES trial was a 12-week, parallel-group, single-blind randomized controlled trial in 33 female and male participants with moderate to severe depression.

    “One of the first intervention studies performed to date, the SMILES trial, involved a 12-week, parallel-group, single-blind randomized controlled trial (RCT) in 33 female and male participants with moderate to severe depression.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [72] Berk M, Jacka FN. Diet and depression-from confirmation to implementation. JAMA. 2019;321:842–3. source

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    Premisecitation

    Consuming folate, zinc and magnesium is inversely associated with depressive disorders, whereas omega-3 fatty acids are inversely related to anxiety disorders.

    “Consuming folate, zinc and magnesium is inversely associated with depressive disorders, whereas omega-3 fatty acids are inversely related to anxiety disorders.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [67] Jacka FN, Maes M, Pasco JA, Williams LJ, Berk M. Nutrient intakes and the common mental disorders in women. J Affect Disord. 2012;141:79–85. source

      Not checked in the free run.

    • cites [68] Jacka FN, Pasco JA, Williams LJ, Meyer BJ, Digger R, Berk M. Dietary intake of fish and PUFA, and clinical depressive and anxiety disorders in women. Br J Nutr. 2013;109:2059–66. source

      Not checked in the free run.

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    Premisecitation

    Secondary BA levels were associated with the progression of AD symptoms from mild to severe, with higher levels of secondary BAs being correlated with worse cognitive function.

    “Secondary BA levels were associated with the progression of AD symptoms from mild to severe, with higher levels of secondary BAs being correlated with worse cognitive function [79].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [79] MahmoudianDehkordi S, Arnold M, Nho K, Ahmad S, Jia W, Xie G. et al. Altered bile acid profile associates with cognitive impairment in Alzheimer’s disease-An emerging role for gut microbiome [published correction appears in Alzheimers Dement. 2019 Apr;15(4):604]. Alzheimers Dement. 2019;15:76–92. source

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    Premisecitation

    AD patients have decreased levels of systemic primary BAs and enhanced levels of distinct secondary BAs compared to healthy controls, which are directly correlated with impairments in cognitive functioning and brain glucose mechanism.

    “AD patients have been found to demonstrate decreased levels of systemic primary BAs and enhanced levels of distinct secondary BAs (the product of gut microbial metabolism) when compared to healthy controls, which are directly correlated with impairments in cognitive functioning and brain glucose mechanism [79].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [79] MahmoudianDehkordi S, Arnold M, Nho K, Ahmad S, Jia W, Xie G. et al. Altered bile acid profile associates with cognitive impairment in Alzheimer’s disease-An emerging role for gut microbiome [published correction appears in Alzheimers Dement. 2019 Apr;15(4):604]. Alzheimers Dement. 2019;15:76–92. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The HELFIMED study found a significant reduction in depression, which directly correlated with increased adherence to the Mediterranean diet over 3-months as well as 6-months.

    “The results of this study indicated a significant reduction in depression, which directly correlated with increased adherence to the Mediterranean diet over 3-months as well as 6-months.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1] Parletta N, Zarnowiecki D, Cho J, Wilson A, Bogomolova S, Villani A. et al. A Mediterranean-style dietary intervention supplemented with fish oil improves diet quality and mental health in people with depression: a randomized controlled trial (HELFIMED). Nutr Neurosci. 2019;22:474–87. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In a secondary analysis of the PREDIMED study, the average risk for depression for the intervention group was 20% lower, but not statistically significant.

    “Even though not statistically significant, the average risk for depression for the intervention group was 20% lower.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [3] Sánchez-Villegas A, Martínez-González MA, Estruch R, Salas-Salvadó J, Corella D, Covas MI. et al. Mediterranean dietary pattern and depression: the PREDIMED randomized trial. BMC Med. 2013;11:208. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In the subset of patients with type-2 diabetes in PREDIMED, the risk for depression was 40% lower in the intervention group compared to the control group, which was statistically significant.

    “However, in the subset of patients with type-2 diabetes, the risk for depression was 40% lower in the intervention group when compared to the control group, which was found to be statistically significant.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [3] Sánchez-Villegas A, Martínez-González MA, Estruch R, Salas-Salvadó J, Corella D, Covas MI. et al. Mediterranean dietary pattern and depression: the PREDIMED randomized trial. BMC Med. 2013;11:208. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    As bile acid synthesis is crucially dependent on dietary factors, and secondary bile are exclusively generated by certain gut microbes, these findings suggest a possible role of diet and the gut microbiome in the observed alterations in the ratio between primary and secondary BAs.

    “As bile acid synthesis is crucially dependent on dietary factors, and as secondary bile are exclusively generated by certain gut microbes, these findings suggest a possible role of diet and the gut microbiome in the observed alterations in the ratio between primary and secondary BAs.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [79] MahmoudianDehkordi S, Arnold M, Nho K, Ahmad S, Jia W, Xie G. et al. Altered bile acid profile associates with cognitive impairment in Alzheimer’s disease-An emerging role for gut microbiome [published correction appears in Alzheimers Dement. 2019 Apr;15(4):604]. Alzheimers Dement. 2019;15:76–92. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    The benefits of a largely plant-based diet in depression likely include anti-inflammatory effects mediated by increased production of SCFAs and polyphenols, an improvement of intestinal permeability and a resulting reduction in metabolic endotoxemia.

    “In summary, the benefits of a largely plant-based diet in depression summarized above is likely to include anti-inflammatory effects mediated by increased production of SCFAs and polyphenols, an improvement of intestinal permeability and a resulting reduction in metabolic endotoxemia.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    Evidence from preclinical, epidemiological, and a limited number of intervention studies supports the concept that a largely plant-based diet, like the Mediterranean diet is conducive to improved cognition, and a reduction in cognitive decline.

    “In summary, evidence from preclinical, epidemiological, and a limited number of intervention studies supports the concept that a largely plant-based diet, like the Mediterranean diet is conducive to improved cognition, and a reduction in cognitive decline.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    These clinical benefits are associated with a reduction in levels of certain secondary BAs, alterations in brain structure, and positive changes in gut microbial composition.

    “These clinical benefits are associated with a reduction in levels of certain secondary BAs, alterations in brain structure, and positive changes in gut microbial composition.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    In the NUAGE study, dietary adherence to a Mediterranean diet was correlated with specific bacterial taxa which were negatively associated with inflammatory markers and also positively associated with markers of low frailty.

    “Results of this study showed that dietary adherence to a Mediterranean diet was correlated with specific bacterial taxa which were negatively associated with inflammatory markers and also positively associated with markers of low frailty.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [6] Ghosh TS, Rampelli S, Jeffery IB, Santoro A, Neto M, Capri M. et al. Mediterranean diet intervention alters the gut microbiome in older people reducing frailty and improving health status: the NU-AGE 1-year dietary intervention across five European countries. Gut. 2020;69:1218–28. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    ASD is often comorbid with gastrointestinal symptoms, anxiety and immune dysregulation.

    “ASD is often comorbid with gastrointestinal symptoms, anxiety and immune dysregulation [104].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [104] McElhanon BO, McCracken C, Karpen S, Sharp WG. Gastrointestinal symptoms in autism spectrum disorder: a meta-analysis. Pediatrics. 2014;133:872–83. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In twelve children with DRE before and after three months on the ketogenic diet, taxonomic and functional profiles were altered, but alpha diversity did not change significantly; relative abundance of the butyrate producing taxa bifidobacteria, E. rectale, and Dialister were significantly diminished, while E. coli was increased.

    “While taxonomic and functional profiles were altered, alpha diversity did not change significantly during the dietary intervention. Relative abundance of the butyrate producing taxa bifidobacteria, E. rectale, and Dialister were significantly diminished during the intervention, while E. coli was increased [128].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [128] Lindefeldt M, Eng A, Darban H, BjerknerA, Zetterstrom CK, Allander T. et al. The ketogenic diet influences taxonomic and functional composition of the gut microbiota in children with severe epilepsy. NPJ Biofilms Microbiomes. 2019;5:5. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In six patients with DRE and glucose transporter type 1 deficiency syndrome who followed the ketogenic diet for three months, reverse transcription polymerase chain reaction analysis of the fecal microbial profiles showed no change in Firmicutes or Bacteroides while showing a significant increase in Desulfovibrio spp.

    “In six patients with DRE and glucose transporter type 1 deficiency syndrome who followed the ketogenic diet for three months, reverse transcription polymerase chain reaction analysis of the fecal microbial profiles showed no change in Firmicutes or Bacteroides while showing a significant increase in Desulfovibrio spp, which is involved in gut mucosal inflammation [127].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [127] Tagliabue A, Ferraris C, Uggeri F, Trentani C, Bertoli S, de Giorgis V. et al. Short-term impact of a classical ketogenic diet on gut microbiota in GLUT1 deficiency syndrome: a 3-month prospective observational study. Clin Nutr ESPEN. 2017;17:33–37. source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Study design and conductreasoning

    Due to the small sample size and the lack of blinding and randomization in most of these studies, dietary interventions in the treatment of ASD remain to be further researched in well-controlled, large-scale trials.

    “However, due to the small sample size and the lack of blinding and randomization in most of these studies, dietary interventions in the treatment of ASD remain to be further researched in well-controlled, large-scale trials.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    A study with ASD children undergoing Microbial Transfer Therapy (MTT) found a significant sustained decrease in both GI and ASD symptoms and confirmed favorable changes in the abundance of certain beneficial bacterial taxa, including Bifidobacteria, Prevotella, and Desulfovibrio.

    “A study with ASD children undergoing MTT found a significant sustained decrease in both GI and ASD symptoms and confirmed favorable changes in the abundance of certain beneficial bacterial taxa, including Bifidobacteria, Prevotella, and Desulfovibrio [113, 122].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [113] Kang DW, Adams JB, Gregory AC, Borody T, Chittick L, Fasano A. et al. Microbiota transfer therapy alters gut ecosystem and improves gastrointestinal and autism symptoms: an open-label study. Microbiome. 2017;5:10. source

      Not checked in the free run.

    • cites [122] Kang DW, Adams JB, Coleman DM, Pollard EL, Maldonado J, McDonough-Means S. et al. Long-term benefit of Microbiota Transfer Therapy on autism symptoms and gut microbiota. Sci Rep. 2019;9:5821. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    Dietary interventions as assessed in these small-scale, poorly controlled clinical studies suggest that a gluten-free, casein-free diet may produce positive effects on symptomatology and severity in some ASD patients, as well as improvements in comorbid GI problems.

    “In summary, dietary interventions as assessed in these small-scale, poorly controlled clinical studies suggest that a gluten-free, casein-free diet may produce positive effects on symptomatology and severity in some ASD patients, as well as improvements in comorbid GI problems.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationcitation

    Altogether, these studies suggest that ASD core symptoms as well as associated comorbid conditions can be improved through comprehensive dietary treatment interventions, the definite cause of which has yet to be identified and may include but not be limited to changes in the gut microbiome.

    “Altogether, these studies suggest that ASD core symptoms as well as associated comorbid conditions can be improved through comprehensive dietary treatment interventions, the definite cause of which has yet to be identified and may include but not be limited to changes in the gut microbiome.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    Translatability of preclinical findings into human psychiatric diseases has been challenging in part due to heterogeneity of human study populations, interindividual differences in genetic vulnerability, confounding environmental factors and considerable differences in structure and function between the human and mouse brain.

    “the translatability of preclinical findings into human psychiatric diseases has been challenging in part due to heterogeneity of human study populations, interindividual differences in genetic vulnerability, confounding environmental factors and considerable differences in structure and function between the human and mouse brain.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    There is a paucity of high quality, randomized controlled clinical trials, and with the exception of a few studies in depression, cognitive decline and in intractable epilepsy, there is relatively little evidence to date that such dietary interventions show a significant therapeutic benefit.

    “However, there is a paucity of high quality, randomized controlled clinical trials, and with the exception of a few studies in depression, cognitive decline and in intractable epilepsy, there is relatively little evidence to date that such dietary interventions show a significant therapeutic benefit.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Premisenone given

    The assessment of dietary habits in most studies has relied on questionnaire data which have been notoriously unreliable.

    “The assessment of dietary habits in most studies has relied on questionnaire data which have been notoriously unreliable.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    A case-control study on 14 children with DRE and 30 healthy controls showed that a ketogenic diet for a week led to a 50% reduction in seizure frequency in infants, associated with decreased levels of Proteobacteri (Cronobacter) and increased levels of beneficial Bacteroidetes taxa (Bifidobacterium, Bacteroides, and Prevotella) compared to baseline, correlating with suppression of seizure activity

    “A case‐control study on 14 children with DRE and 30 healthy controls showed that a ketogenic diet for a week led to a 50% reduction in seizure frequency in infants, associated with decreased levels of Proteobacteri (Cronobacter) and increased levels of beneficial Bacteroidetes taxa (Bifidobacterium, Bacteroides, and Prevotella) compared to baseline, correlating with suppression of seizure activity”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [108] Xie G, Zhou Q, Qiu CZ, Dai WK, Want HP, Li YH. et al. Ketogenic diet poses a significant effect on imbalanced gut microbiota in infants with refractory epilepsy. World J Gastroenterol. 2017;23:6164–71. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    When viewed together, there is emerging but mixed clinical evidence tying the ketogenic diet to changes in the gut microbiota and improvements in seizure activity in subsets of patients.

    “When viewed together, there is emerging but mixed clinical evidence tying the ketogenic diet to changes in the gut microbiota and improvements in seizure activity in subsets of patients.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The intake of a consortium of butyrate producers may improve metabolic abnormalities and reduce systemic immune activation.

    “For example, the intake of a consortium of butyrate producers may improve metabolic abnormalities and reduce systemic immune activation [135].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [135] Perraudeau F, McMurdie P, Bullard J, Cheng A, Cutcliffe C, Deo A. et al. Improvements to postprandial glucose control in subjects with type 2 diabetes: a multicenter, double blind, randomized placebo-controlled trial of a novel probiotic formulation. BMJ Open Diabetes Res Care. 2020;8:e001319 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Premisenone given

    Diagnostic testing of the gut microbiome to develop personalized dietary approaches, or to determine the future risk for the development of chronic brain disorders is in its early stages, and the benefits of such testing have not been demonstrated in prospective, longitudinal studies.

    “Diagnostic testing of the gut microbiome to develop personalized dietary approaches, or to determine the future risk for the development of chronic brain disorders is in its early stages, and the benefits of such testing have not been demonstrated in prospective, longitudinal studies.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    The evaluation of the potential therapeutic benefit of fecal microbial transplants in brain disorders, mimicking such effects previously reported in animal models has shown inconsistent and time limited success, with the exception of the study in ASD discussed earlier.

    “The evaluation of the potential therapeutic benefit of fecal microbial transplants in brain disorders, mimicking such effects previously reported in animal models has shown inconsistent and time limited success [123], with the exception of the study in ASD discussed earlier.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [123] Chinna Meyyappan A, Forth E, Wallace CJK, Milev R. Effect of fecal microbiota transplant on symptoms of psychiatric disorders: a systematic review. BMC Psychiatry. 2020;20:229. source

      Not checked in the free run.

55 of 55

  • The paper relies on this without support.

    Sufficient scientific evidence from preclinical and clinical studies is available to suggest a causative role for diet and the microbiome in the selected psychiatric disorders.

    “From the large number of psychiatric disorders which have been associated with diet and the microbiome, we have limited the discussion to those disorders for which sufficient scientific evidence from preclinical and clinical studies is available to suggest a causative role.”

  • The paper relies on this without support.

    Serotonin production and release in the enteric nervous system is greatly influenced by dietary choices, with the amounts of complex carbohydrates and tryptophan contained in the diet being the most important factors.

    “Serotonin production and release in the enteric nervous system is greatly influenced by dietary choices as well, with the amounts of complex carbohydrates and tryptophan contained in the diet being the most important factors.”

  • The paper relies on this without support.

    Certain dietary micronutrients such as zinc, omega-3 fatty acids, folate, and B vitamins may further influence brain development and function.

    “Certain dietary micronutrients such as zinc, omega-3 fatty acids, folate, and B vitamins may further influence brain development and function”

  • The paper relies on this without support.

    The lack of certain dietary micronutrients can result in mental dysfunction and contribute to the development of brain disorders.

    “the lack of which can result in mental dysfunction and contribute to the development of brain disorders.”

  • The paper relies on this without support.

    Risk genes predisposing for the development of ASD have not changed during the past decades.

    “As risk genes predisposing for the development of ASD have not changed during the past decades”

  • The paper relies on this without support.

    Results from high-quality randomized controlled trials demonstrating benefits beyond adherence to a largely plant-based diet by the intake of supplementary pre-, pro- or postbiotics are currently not available.

    “Results from high quality RCTs demonstrating benefits beyond adherence to a largely plant based (“microbiome-friendly”) diet by the intake of supplementary pre-, pro- or postbiotics are currently not available.”

  • The paper relies on this without support.

    A majority of researchers and practitioners share the prevalent mindset that psychiatric disorders are diseases of the brain and do not involve the gut and its microbiome.

    “One of the major challenges of Nutritional Psychiatry Research is to gradually change the prevalent mindset shared by a majority of researchers and practitioners that psychiatric disorders are diseases of the brain, and do not involve the gut and its microbiome.”

  • The paper relies on this without support.

    The therapeutic benefits of specific dietary interventions have not been clearly established.

    “Until an objective’s therapeutic benefits of specific dietary interventions have clearly been established, effective treatments are limited to the general recommendation of a healthy, largely plant-based diet with high variety of fruit and vegetables, or a ketogenic diet in some instances.”
8 of 8

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • The positive effects of a GM-favorable diet are likely due to the availability of prebiotics, probiotics, SCFAs, and polyphenols.

    “This is likely due to the availability of prebiotics, probiotics, SCFAs, and polyphenols.”

    From Signalling cognition: The gut microbiota and hypothalamic-pituitary-adrenal axis (2023) · cites this paper as [509]

  • A significant body of evidence demonstrates that consuming a GM-favorable diet can positively influence the GM, improve health status, and enhance cognitive function.

    “A comprehensive review of this topic is beyond the scope of this review, however, a significant body of evidence demonstrates that consuming a GM-favorable diet can positively influence the GM, improve health status, and enhance cognitive function (506–510).”

    From Signalling cognition: The gut microbiota and hypothalamic-pituitary-adrenal axis (2023) · cites this paper as [509]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Cited preclinical finding runs counter to claimed cognitive improvement

    Minor

    The text presents references 89-94 as preclinical findings consistent with improved cognition and memory, but reference 93 is titled as finding detrimental cognitive effects of the ketogenic diet.

  • Epilepsy RCT count differs between table and text

    Minor

    The table reports a meta-analysis of 10 RCTs, while the text describes 10 RCTs in children plus one in adults, for a total of 11.

2 of 2

The citation lists haven’t been fetched yet

References 135 · Cited by 193

Authors
Horn, J., Mayer, D. E., Chen, S., & Mayer, E. A.
Affiliations
  • University of California, Los Angeles (US)
  • Los Angeles Police Department (US)
  • University of California, San Francisco (US)
Corresponding author
Mayer, E. A.
ORCID
Venue
Translational Psychiatry
Publisher
Springer Science and Business Media LLC
Published
2022-04-20
Volume
12
Issue
1
Pages
164-164
ISSN
2158-3188 (ISSN-L)
DOI
10.1038/s41398-022-01922-0
PMC
PMC9021202
OpenAlex
W4224234335
Semantic Scholar
683152ff6ed671f1a7798341a94a5161107fd225
Cited by
193
References
135
Citations by year
2026: 38 · 2025: 50 · 2024: 60 · 2023: 39 · 2022: 6
FWCI
4.03
Type
journal article
Language
en
Open access
Licence
Locations
  • Translational Psychiatry (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • eScholarship (California Digital Library) (submittedVersion, cc-by)
Funders
  • National Institutes of Health (R01 DK064539, DK064539, DK048351)
  • National Institute of Diabetes and Digestive and Kidney Diseases (R01DK048351, P50DK064539, P30DK041301)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Gut microbiota and health
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Nutritional Studies and Diet
  • Health Sciences › Medicine › Gastroenterology › Gastrointestinal motility and disorders
Keywords
diet, gut microbiota, gut-brain axis, mental illness, depression, cognitive decline, Parkinson's disease, autism spectrum disorder, epilepsy, dietary fiber, polyphenols, microbial metabolites, anti-inflammatory activity, neuroinflammation
MeSH terms
Autism Spectrum Disorder, Gastrointestinal Microbiome, Mental Disorders, Brain, Brain Diseases, Cross-Sectional Studies, Diet, Epilepsy, Humans

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Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-09.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-09.

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