In plain terms

The claim being assessed: The composition of the human gut microbiome is a primary, targetable causal driver of systemic and neurobehavioural disease.

Where the evidence stands: Γ — Plausible mechanism. There is a believable biological story and partial support, but the causal step has not been demonstrated.

What this mechanism does: This makes the process worse or keeps it going, but something else starts it.

Strongest evidence for it: SC4 is the preregistered human-primacy gate. Transfers, defined strains and microbial products show real bounded contributions, and HE intervention crosses human contribution thresholds, but none establishes composition as the primary upstream target across systemic and neurobehavioural disease. SC1 association is Β, bounded rodent causality SC2 Ζ, human contribution SC3 Ε, broad primacy SC4 Γ. These are different scopes, not a refutation of the microbiome.

What decisive evidence would look like

In plain terms, researchers would change the proposed cause, confirm it changed as intended, and measure a meaningful health outcome while checking other explanations. The result should be able to support or count against the claim.

Relative explanatory fit: Alternative ranked ahead

What this review means

Gut microbes differ between people and can affect metabolism or behavior in experiments. This review asks when those effects contribute to human disease and whether microbiome composition is a primary cause across diseases.

Implications for health and treatment: SC4 is the preregistered human-primacy gate. Transfers, defined strains and microbial products show real bounded contributions, and HE intervention crosses human contribution thresholds, but none establishes composition as the primary upstream target across systemic and neurobehavioural disease. SC1 association is Β, bounded rodent causality SC2 Ζ, human contribution SC3 Ε, broad primacy SC4 Γ. These are different scopes, not a refutation of the microbiome.

Limits for individual care: 67 primary reports with 8 selected partial-body examinations; density, heterogeneous controls and incomplete access set the confidence, not correctness. The grade applies to the exact registered claim; stronger findings for narrower subclaims remain separate. No complete-paper audit or blinded calibration is claimed. This educational review does not establish an individual treatment recommendation.

Medical information notice: This review provides general health information, not medical advice. It cannot diagnose a condition or replace an individual discussion with a qualified clinician.

Source checking used complete abstracts/status records and selected original partial-body passages. No complete-paper audit or independent scientific peer review is claimed. Detailed access counts and limitations appear in the review.

A low grade is not an accusation. It means the causal work has not been done yet, which is the ordinary state of most actively studied mechanisms in biology.

At a glance

Sub-claims assessed separately

Figures

Explanatory figures summarizing this review. They carry no evidential weight of their own; where a figure and the review differ, the review governs.

Full assessment

From here the review is written for a technical reader: caps and thresholds, competing models, the independence basis, and the citation ledger.

Sources: 67 primary reports; claims: 72; verified: 72; unverified: 0. Verification is bounded attribution. Access: 8 partial-body and 59 complete abstract/status examinations. Literature cutoff: 2026-10-08; source examination UTC date: 2026-10-09. No complete-paper audit or blinded calibration claimed. Adversarial review: Generated by Sol 6.1; adversarially reviewed by Claude Opus 5.5 (Anthropic) on 2026-10-14. 3 corrections applied (see ADVERSARIAL REVIEW AND APPROVAL). Status: Approved as revised.

AT A GLANCE

Microbial causality is established in defined animal contexts and some human interventions; broad human compositional primacy remains unestablished.

Deciding experiment: Run preregistered diagnosis-specific factorial trials of a defined strain/enzyme consortium and matched control, crossed with controlled dietary substrate, while measuring bowel transit and fixing baseline drugs. Use baseline factor abundance for enrollment, retain nonresponders, and assess mechanistic mediation and durable clinical endpoints.

Belief versus evidence: SC4 is the preregistered human-primacy gate. Transfers, defined strains and microbial products show real bounded contributions, and HE intervention crosses human contribution thresholds, but none establishes composition as the primary upstream target across systemic and neurobehavioural disease. SC1 association is Β, bounded rodent causality SC2 Ζ, human contribution SC3 Ε, broad primacy SC4 Γ. These are different scopes, not a refutation of the microbiome.

Best-supported rival: Diet/substrate-dependent microbial contribution. Factorial diet-by-defined-community human trials, with transit/medication held stable and host pathways measured, separate an active microbial contribution from host-driven signature change. No complete pan-disease separating study is in this corpus.

COMPETING MECHANISTIC MODELS

Rank 1: Diet/substrate-dependent microbial contribution (Ε). Host diet and microbial function interact; neither alone is a universal primary switch. Ridaura diet-dependent rescue and carbohydrate/SCFA/host-pathway experiments directly discriminate substrate conditions (PMID24009397,24412651,36041436). Defined host contexts and human factor trials are incomplete; a flexible interaction model must make factor-specific predictions.

Rank 2: Disease/transit/medication-dependent microbiome (Β). Disease features, treatment and transit reshape community signatures. Metformin stratification, dietary intervention and stool-consistency studies explain important signature variance (PMID26633628,24336217,26069274,34767757). FMT/defined-factor functional effects prevent reducing every microbial feature to a passive consequence (PMID39800192,20620945).

Rank 3: Rodent-context microbial causality (Ζ). Specific microbial factors can be causal inside predefined genotypes and diets. SFB arthritis, ketogenic diet colonization and targeted TMA inhibition cross defined functional boundaries (PMID20620945,29804833,26687352). Human trials and developmental/context differences limit translation (PMID39073834,32150549).

Rank 4: Host-genetic and immune-state common causes (Β). Host traits influence both disease and microbial ecology. Leptin-null ecology, host-autoantigen dependence and host-genetic association provide plausible common causes (PMID16033867,22031325,33462485). Host-genetic association alone cannot exclude controlled microbial contribution.

Rank 5: Primary gut-microbiome driver (Γ). Composition is the broad primary upstream, targetable human disease cause. Transfer and human HE recurrence evidence supply a strong case for component causality (PMID24009397,39800192). Broad primacy fails to account for host/diet dependence, null functional trials and product effects without global community change (PMID32150549,34767757,31263284).

The tournament does not alter the nominal level. Compatible pathways and flexible alternatives are not automatically proved by explaining observations.

FULL REVIEW

Registered claim and scope

The composition of the human gut microbiome is a primary, targetable causal driver of systemic and neurobehavioural disease.

The ranking title is a methodological problem; grade the index causal-primacy proposition, not the existence of the microbiome or the methodological critique. Human systemic and neurobehavioural disease scope is gated by SC4; rodent causality and human contribution are distinct scopes. C. difficile eradication is an out-of-scope calibration comparator, not support for systemic primacy.

Selection: public-interest rank 41 from the editorial ranking compiled 2026-09-23; categorical prior verdicts were visible. Private fresh review; earlier documents are preserved.

Evidence and causal interpretation

Composition-disease association is real in multiple cohorts, but a taxonomic signature is an observation rather than a driver. Deep PD/diabetes/cardiovascular studies identify candidate pathways (PMID36376318,23023125,29018189); diversity and gene richness add prediction (PMID23985870). Population studies show strong medication, diet and stool-consistency relationships; absolute profiling exposes relative-abundance artifacts and extraction experiments expose processing effects (PMID27126039,27126040,26069274,29143816,32374853). These are necessary design controls, not reasons to deny all microbial function.

Controlled transfer makes a substantially stronger animal case. Turnbaugh transmits adiposity in germ-free mice; Ridaura transmits discordant-twin and cultured-community phenotypes and maps diet-dependent rescue (PMID17183312,24009397). Original Ridaura text shows rescue fails under high-saturated-fat/low-fruit-and-vegetable diet, and early glucose findings do not demonstrate full insulin resistance. Leptin-null ecology and diet perturbation identify reverse directions too (PMID16033867,24336217).

Defined microbes and host epistasis show bounded causal mechanisms. A single SFB reinstates arthritis in K/BxN recipients and IL-17 neutralization prevents disease; Clostridium/Treg and ketogenic-diet consortia establish other defined immune/neurological functions (PMID20620945,21205640,29804833,19836068). Intestinal-gluconeogenesis loss abolishes SCFA/fiber metabolic benefit despite similar community changes (PMID24412651). Dietary sugar disrupts a protective microbe-Th17 interaction rather than producing an autonomous microbial initiator (PMID36041436).

The gut-brain studies need phenotype discipline. Original Hsiao results show B.fragilis leaves social deficits, and 4EPS induces anxiety/startle changes without repetitive or communicative defects (PMID24315484). Original Sharon results identify donor/sex/age effects and prenatal/weaning-dependent metabolite rescue; juvenile-only BTBR treatment fails (PMID31150625). Stress-circuit and maternal-neurodevelopment rescue identify plausible host routes; depression-donor transfers change recipient behavior but do not identify the cause of human depression (PMID34194038,32968276,27491067,27067014).

Original Sampson results restrict the motor effects of microbial recolonization and SCFA to Thy1-alpha-synuclein overexpression; WT donor recipients lack notable motor effects and donor pairs vary (PMID27912057). Microbial levodopa metabolism can change drug exposure without initiating PD (PMID31196984). Human PD trials must therefore distinguish constipation, drug response, symptomatic motor change and neurodegeneration.

Human contribution is more than a speculative possibility. HE FMT studies use patients with baseline cirrhosis and recurrent HE; original Bajaj text reveals antibiotic pretreatment only in the active arm and unchanged ongoing lactulose/rifaximin (PMID28586116). Capsule placebo comparison improves cognitive testing but has similar HE/infection episodes (PMID31038755). THEMATIC adds blinded placebo comparison and lower recurrence in its post hoc any-FMT comparison; the multi-omic follow-up is the same trial and its molecular predictors remain associations (PMID39800192,41503571). This supports a context-specific therapeutic contribution, not microbial initiation of cirrhosis.

Metabolic trials are mixed. Lean-donor FMT improves short-term clamp sensitivity, with loss of effect by later follow-up in Kootte; FMT-TRIM shows engraftment without significant metabolic benefit, and placebo-controlled antibiotics show community change without relevant metabolic improvement (PMID22728514,28978426,32150549,27411009). Vancomycin lowers sensitivity in a smaller active-comparator study, while vegan FMT fails to change TMAO or vascular-inflammatory endpoints (PMID24316517,29581220). These trials cannot be erased by a provider gap matrix.

Pasteurized Akkermansia produces exploratory metabolic signals while overall community structure remains unchanged (PMID31263284); original text identifies HOMA indices, baseline insulin imbalance, unchanged HbA1c and nonsignificant weight/fat effects. Its outer-membrane protein partly recapitulates mouse benefits (PMID27892954). Metformin signatures and microbial mediation are separate: the original Forslund conclusion calls for causal validation, while randomized drug exposure with mouse transfer supports partial mediation without isolating the human microbial component (PMID26633628,28530702).

Clinical neurobehavioural results also map boundaries. GUT-PARFECT finds an off-medication motor change with baseline/covariate adjustment, but no overall MDS-UPDRS or many secondary-domain differences; Finnish FMT finds no primary benefit despite stronger microbial change (PMID38686220,39073834). Smaller trials report PD symptom benefit (PMID38057970,40848995), and ALS FMT does not slow functional decline (PMID39617896). Defined L.reuteri improves social functioning without changing overall ASD severity or microbiome structure; healthy-male JB-1 is a negative translation comparator (PMID38113884,27865949). ASD-related dietary preferences account for some human microbiome associations (PMID34767757).

TMAO demonstrates why factor production and disease primacy differ. Isotope/antibiotic challenge identifies microbial production; human cardiovascular prediction remains observational (PMID23614584). Mouse dietary/carnitine exposure, microbial suppression, platelet assays and nonlethal TMA inhibition establish selected mechanistic effects (PMID21475195,23563705,26972052,26687352). Red-meat diet changes both production and renal handling, and kidney function strongly predicts circulating TMAO (PMID30535398,37730687). Portal ethanol and ADH/antibiotic experiments identify exposure but not liver-trajectory rescue (PMID36216942).

MS studies show microbial factors acting with host immune predisposition: induced-model transfer, discordant-twin transfer into autoreactive transgenics, myelin-antigen cooperation and medication-associated ecology do not demonstrate primary human MS initiation (PMID28893978,28893994,22031325,30568995). Propionate add-on/post hoc course analyses and weak pleiotropic host-genetic instruments are suggestive, not definitive human mechanism isolation (PMID32160527,33462485). The strongest conclusion is plural, context-specific causality; the registered broad compositional-primacy claim remains Gamma.

HYPOTHESIS STATE EVALUATION FRAMEWORK (HSEF v5.3)

Subclaim matrix and aggregation

Preregistered aggregation: scope-matched. SC4 is the preregistered human-primacy gate. Transfers, defined strains and microbial products show real bounded contributions, and HE intervention crosses human contribution thresholds, but none establishes composition as the primary upstream target across systemic and neurobehavioural disease. SC1 association is Β, bounded rodent causality SC2 Ζ, human contribution SC3 Ε, broad primacy SC4 Γ. These are different scopes, not a refutation of the microbiome. Sensitivities: weakest-link Β; primary-subclaim Γ; scope-matched Γ.

Decisive-perturbation inventory and causal tally

[4] THEMATIC compares placebo with capsule/enema FMT in treated cirrhosis and reports lower HE recurrence in a post hoc any-FMT comparison. Safety is primary; recurrence is secondary and its pooled contrast post hoc. Underlying cirrhosis and concurrent drugs remain upstream.

[10] Discordant-twin communities and culture collections transmit body-fat phenotypes; lean-community cohousing rescue depends on diet. Rescue fails on high-saturated-fat/low-fruit-vegetable diet. Early glucose contrast does not establish full insulin resistance; transfer remains recipient-mouse causality.

[16] SCFA/fiber metabolic benefits disappear in intestinal-gluconeogenesis-deficient mice despite similar microbiota changes. Host pathway dependence and administered metabolites establish conditional benefit; endogenous strain necessity remains unspecified.

[21] Bacteroides fragilis improves gut permeability and selected behaviors after maternal immune activation; a metabolite challenge induces some abnormalities. Social deficits persist; 4EPS induces anxiety/startle changes but not repetitive or communicative deficits. Maternal immune activation is upstream and human ASD causality is untested.

[24] Defined Akkermansia/Parabacteroides colonization restores ketogenic-diet seizure protection and transfers protection under control diet. Two mouse seizure contexts support treatment mediation, not universal epilepsy causation. Linked erratum remains attached.

[38] DMB inhibits microbial TMA generation and decreases diet-enhanced atherosclerotic lesions in ApoE-deficient mice. Chemical specificity and selected diet/genotype need controls; no human hard-endpoint trial establishes broad primacy.

[50] Defined L. reuteri combination improves social functioning in ASD while overall autism severity and community composition do not change. Pilot selected-domain benefit does not establish overall ASD treatment, microbial-composition primacy or strain-specific human efficacy.

[67] Single SFB colonization reinstates Th17/autoantibody responses and arthritis in germ-free K/BxN mice; IL-17 neutralization prevents disease. Autoreactive host genotype is prerequisite; single strain is causal within this mouse context, not across human autoimmunity.

Tally: 8 discriminating contrasts. Null and negative contrasts are discriminators, not positive threshold crossings. Reports and replications are not independent causal lines. Eight contrasts are flagged as especially discriminating within their precise scopes; other positive interventions may contribute but are not counted as mechanism-isolating decisive tests. Crude FMT, broad antibiotics, transgene/recipient transfer, administered metabolites and surrogate outcomes do not establish broad human primacy.

Cap audit, precedence and Β/Γ/Δ boundary

Gnotobiotic transfer/addition crosses the microbiome perturbation threshold for recipient rodent SC2. Universal cap 5 blocks transferring that result to endogenous human SC4. FMT with a human functional disease endpoint can cross SC3 within baseline cirrhosis; the cap does not erase this clinical contribution, but treatment benefit does not prove autonomous initiation. Biomarker-only TMAO/ethanol/HOMA results do not alone cross clinical trajectory thresholds.

Gamma hard-rule audit: Association plus cell-culture metabolite assays: cannot carry SC4 beyond Γ. Association plus in vitro immune readouts: cannot carry SC4 beyond Γ. Any framework that has not crossed the transfer/rescue threshold in vivo: not triggered for bounded rodent SC2; human primacy is still separately unproved. Microbial production biomarkers without disease trajectory change do not cross human clinical dependency.

SC1 cap: “Pure association evidence — however large, however replicated — cannot exceed Β.” Disease-associated community features recur, but stool consistency, medication and quantitative measurement substantially alter interpretation; association alone is Β.

SC4 cap: “Seeding or forced-transfer paradigms cap at Γ for endogenous propagation claims. Forced spread is not observed spread.” Diet, host genotype, treatment and transit can precede microbial changes. Community engraftment or changed abundance can occur without functional benefit; targeted products can benefit without changing overall composition. No broad human upstream-primacy contrast closes these alternatives.

SC1 field-valid definition: “ - Gnotobiotic or transfer experiment showing phenotype movement, at minimum - Even without defined-consortium precision or robust rescue, a transfer paradigm in vivo is the minimum that crosses this threshold

Per Cap precedence above, a gnotobiotic or forced-transfer experiment crosses Δ for the recipient-animal subclaim it was actually run in, while universal cap 5 (seeding or forced-transfer paradigms cap at Γ) still blocks the inference from that result to endogenous human biology — score the two scopes separately rather than choosing between the rules.” Positive full-scope result: no. Disease-associated community features recur, but stool consistency, medication and quantitative measurement substantially alter interpretation; association alone is Β.

SC2 field-valid definition: “ - Gnotobiotic or transfer experiment showing phenotype movement, at minimum - Even without defined-consortium precision or robust rescue, a transfer paradigm in vivo is the minimum that crosses this threshold

Per Cap precedence above, a gnotobiotic or forced-transfer experiment crosses Δ for the recipient-animal subclaim it was actually run in, while universal cap 5 (seeding or forced-transfer paradigms cap at Γ) still blocks the inference from that result to endogenous human biology — score the two scopes separately rather than choosing between the rules.” Positive full-scope result: yes. Defined microbial addition/rescue, host-pathway interruption and nonlethal microbial-enzyme inhibition converge on functional rodent effects with distinct failure modes. Genotype, diet and developmental timing remain prespecified boundaries.

SC3 field-valid definition: “ - Gnotobiotic or transfer experiment showing phenotype movement, at minimum - Even without defined-consortium precision or robust rescue, a transfer paradigm in vivo is the minimum that crosses this threshold

Per Cap precedence above, a gnotobiotic or forced-transfer experiment crosses Δ for the recipient-animal subclaim it was actually run in, while universal cap 5 (seeding or forced-transfer paradigms cap at Γ) still blocks the inference from that result to endogenous human biology — score the two scopes separately rather than choosing between the rules.” Positive full-scope result: yes. Human FMT in treated cirrhosis alters recurrence/cognition, with phase 2 placebo-controlled evidence and weaker earlier studies. Metabolic and PD trials are heterogeneous and ALS is negative; a context-specific contribution is supported, not one mechanism across disorders.

SC4 field-valid definition: “ - Gnotobiotic or transfer experiment showing phenotype movement, at minimum - Even without defined-consortium precision or robust rescue, a transfer paradigm in vivo is the minimum that crosses this threshold

Per Cap precedence above, a gnotobiotic or forced-transfer experiment crosses Δ for the recipient-animal subclaim it was actually run in, while universal cap 5 (seeding or forced-transfer paradigms cap at Γ) still blocks the inference from that result to endogenous human biology — score the two scopes separately rather than choosing between the rules.” Positive full-scope result: no. Diet, host genotype, treatment and transit can precede microbial changes. Community engraftment or changed abundance can occur without functional benefit; targeted products can benefit without changing overall composition. No broad human upstream-primacy contrast closes these alternatives.

Upward threshold ladder

SC1 Δ: “Requires a transfer paradigm or causal perturbation in vivo.” Satisfied: no. For a causal interpretation of a particular signature, isolate a strain/factor and show a functional human endpoint; association existence remains a separate claim.

SC2 Δ: “Requires a transfer paradigm or causal perturbation in vivo.” Satisfied: yes.

SC2 Ε: “Requires context-specific causal effect with defined limits. A transferable phenotype exists, but microbial identity or generalizability remains incomplete.” Satisfied: yes.

SC2 Ζ: “Requires: - Defined consortium or strain-level causal evidence - Rescue logic - Replication across at least two relevant models or cohorts” Satisfied: yes.

SC2 Η: “Requires: - Defined consortium or factor rescue in multiple contexts - Narrowed mechanism - Strong exclusion of diet, housing, batch, and handling confounds” Satisfied: no. Replicate strain/factor-rescue mechanisms with native abundance across independently housed genotypes/diets while excluding developmental and chemical-target alternatives.

SC3 Δ: “Requires a transfer paradigm or causal perturbation in vivo.” Satisfied: yes.

SC3 Ε: “Requires context-specific causal effect with defined limits. A transferable phenotype exists, but microbial identity or generalizability remains incomplete.” Satisfied: yes.

SC3 Ζ: “Requires: - Defined consortium or strain-level causal evidence - Rescue logic - Replication across at least two relevant models or cohorts” Satisfied: no. Prospective factor-defined placebo-controlled trials with durable disease endpoints and host-pathway rescue logic, rather than repeating crude FMT as if it added a new independent line.

SC4 Δ: “Requires a transfer paradigm or causal perturbation in vivo.” Satisfied: no. Prospective before-disease microbial factor manipulation with matched diet, transit, medication and host-genotype controls, showing a substantial durable disease effect across the registered diagnoses.

Upper ladder: Strain-resolved rescue, nonlethal enzyme inhibition, human FMT disease recurrence and host-genetic instruments were considered. Independent rodent classes support SC2 Ζ. Human trials establish bounded contribution but crude-community modality replication and metabolic surrogates cannot carry SC4 to Ζ; weak association is not re-capped over genuine convergence.

Independence: SC2 receives Ζ from functionally distinct controlled microbial/host perturbations whose principal errors differ, not from labs, repeated transfer cohorts or multiple papers. Human FMT studies are one crude-community intervention class; THEMATIC molecular follow-up is the same trial. Human genetics remains limited by weak, pleiotropic compositional instruments.

Defined microbial colonization with host-immune epistasis [67, 24]: Excludes mere donor disease correlation by controlled addition and relevant host dependence, while retaining gnotobiotic developmental confounding.

Nonlethal microbial enzyme inhibition in conventional animals [38]: Tests metabolic contribution without germ-free development or entire-community removal; chemical off-target specificity remains a different vulnerability.

Host intestinal pathway interruption under matched microbial changes [16]: Demonstrates host-pathway requirement despite similar community changes, excluding abundance alone as the functional explanation.

Falsification and pitfalls

Phenotype fails to transfer or change despite community manipulation in defined human regimens. FMT-TRIM, vegan FMT, placebo-controlled antibiotics and Finnish PD FMT show engraftment/compositional or metabolic shifts without the requested clinical/physiological benefit (PMID32150549,29581220,27411009,39073834). Additional downgrade: False.

Host and substrate prerequisites constrain transfer/rescue. Ridaura diet blocks cohousing rescue; Sampson WT animals lack the ASO motor phenotype; human ASD diet links and metformin signatures challenge autonomous primacy (PMID24009397,27912057,34767757,26633628). Additional downgrade: False.

Dysbiosis treated as mechanism. Abundance, diversity and inferred neuroactive functions are separated from functional factor perturbation.

Transfer generalized to endogenous human initiation. Recipient mouse disease or behavior cannot establish donor human disease causality.

Biomarker change treated as clinical dependency. TMAO, ethanol and HOMA changes are not cardiovascular events, liver progression or neuron preservation.

Negative perturbation counted as positive threshold. Null human trials are discriminators, excluded from the positive tally.

Outcome-fitted scope and report independence. No responder-defined enrollment; THEMATIC secondary analysis and shared cohort reanalyses remain linked.

Provider gap absence treated as field absence. Consensus metabolic-trial gap was contradicted by retrieved primary trials; its meter/headline are not evidence.

Adversarial steelman: above, then below

One rung above Γ would be Δ for SC4: human FMT and defined microbial products provide an earnest intervention-based case that the community is an upstream driver. The HE recurrence result is stronger than a diversity association and deserves causal credit.

One rung below Γ would be Β if human microbiome primacy rests only on disease-associated abundance signatures. Diet, drugs, stool consistency and negative transplant trials make that an intellectually serious alternative.

Δ for broad primacy is rejected because the human trials treat established host disease and do not isolate a primary compositional initiator. Β understates actual controlled factor/transfer mechanisms that provide partial system support. Scoped contribution retains its separate Ε/Ζ scores.

Final score, causal direction and M/S/D

SC4 is the preregistered human-primacy gate. Transfers, defined strains and microbial products show real bounded contributions, and HE intervention crosses human contribution thresholds, but none establishes composition as the primary upstream target across systemic and neurobehavioural disease. SC1 association is Β, bounded rodent causality SC2 Ζ, human contribution SC3 Ε, broad primacy SC4 Γ. These are different scopes, not a refutation of the microbiome.

Within documented disease contexts, microbial factors modify a process initiated by diet, immune activation, host autoreactivity, cirrhosis or an alpha-synuclein transgene. They can amplify or maintain phenotype. No universal initiation-plus-removal-plus-rate-limiting demonstration establishes a primary-driver role; this direction judgment is not inferred from tournament rank.

Momentum: Mechanistic only. Active work is clinical rather than boundary-addressing: THEMATIC and recent placebo-controlled PD/ALS/defined-L.reuteri studies test functional human boundaries in established disease (PMID39800192,39073834,39617896,38113884). No currently recruiting trial is claimed, and none of these designs is the before-disease factor manipulation that SC4's next threshold requires, so the value is Mechanistic only rather than Decisive work underway.

Stability: Stable. No named pending result is claimed likely to change the broad primary-driver gate imminently; specific future human factor trials could raise scoped contribution.

Divergence: Contested; no single implied-level arithmetic. These dimensions do not change level or confidence.

PROPOSED DECISIVE EXPERIMENTS

Run preregistered diagnosis-specific factorial trials of a defined strain/enzyme consortium and matched control, crossed with controlled dietary substrate, while measuring bowel transit and fixing baseline drugs. Use baseline factor abundance for enrollment, retain nonresponders, and assess mechanistic mediation and durable clinical endpoints.

Readout: HE recurrence or another prespecified diagnosis-specific clinical trajectory, native microbial-factor activity and host-pathway engagement over a registered horizon. Controls: Inactive factor/strain control, equivalent bowel preparation, substrate matching, stable host drugs, transit measurements, blinded outcomes and dose-matched functional rescue. Supporting: Selective factor correction improves the registered disease endpoint with specific mediation across substrate/genotype strata and persists beyond transient engraftment. Falsifying: Verified factor engagement changes only composition/metabolites, benefit disappears after diet/drug matching, or relevant human functional outcomes remain unchanged.

RESEARCH TIMELINE

KNOWLEDGE GAPS

Identify factor/strain necessity separately from crude donor-community sufficiency.

Resolve placebo, bowel-cleansing, antibiotic-pretreatment and autologous-stool effects in PD FMT.

Test durable hard-endpoint benefit of microbial enzyme inhibition in humans rather than extrapolating TMAO concentration.

Separate host metabolic effects of pasteurized bacteria from correction of community composition.

Prospectively validate baseline predictors without selecting responders after outcomes.

Test human developmental timing and phenotype domains instead of labeling mouse anxiety as autism.

Quantify transit and absolute microbial load alongside drugs, diet and strain function.

Partition shared trials and reused metagenomes before claiming independent convergence.

METHODS AND CONSENSUS CONTRIBUTION

Consensus was used through the signed-in browser for discovery, counterevidence, research-gap and timeline suggestions, and attempted checks of specific indexed full-text passages. Provider statements about Methods/Results and any returned passages were compared with original-paper passages where available; failed retrievals, source substitutions and unverified aspects are recorded in the case reconciliation. Successful original-passage comparisons are distinguished from provider summaries and assertions of access. Provider screening counts, citation counts and meters were not used as primary counts or HSEF scores. This source log records access depth; it does not claim complete-paper or supplement review. The monthly API allowance was conserved: zero Consensus API calls in this batch.

REVIEWER NOTES

This ranking entry originally names a methodological problem. The prose and score attach to its explicit causal restatement. Consensus yielded useful check prompts and admitted inaccessible originals but also source substitutions, missing metabolic trials, and an inconsistent headline/meter. Four provider passage/anchor aspects were compared with originals; eight papers received selected original-body checks. SciSpace leads were predominantly reviews/chapters and do not add primary count. Scite metadata/citation-context inspection is separately recorded and does not set a score. Correction metadata was checked; correction bodies and supplements were not comprehensively audited. Prior ranking categorical verdict/index framing were visible; inherited calibration is disclosed and this is not blinded.

Search leads, reviews, protocols and correction notices do not pad the primary count. Downloaded XML does not earn examination credit. Linked notices remain attached; unexamined correction details limit inference. This is a coordinator source/claim consistency assessment, not independent blinded calibration.

ADVERSARIAL REVIEW AND APPROVAL

Authoring model: Sol 6.1. Adversarial reviewer: Claude Opus 5.5 (Anthropic). Date: 2026-10-14.

Scope of checks. PMIDs verified 67/67 against PubMed (title, first author, journal, year, DOI, publication-type flags); no retraction, expression of concern or erratum-of-record flag found on any row, and the seven attached erratum notices remain in their parent rows' status flags rather than taking rows of their own. Load-bearing claims spot-checked against the retrieved abstracts: 15 (PMID 39800192, 28586116, 24009397, 24412651, 20620945, 26687352, 27912057, 38113884, 31263284, 32150549, 39617896, 26069274, 28893994, 22031325, 21475195). Scoring logic checked against the HSEF v5.3 framework file and SKILL.md Steps 2-4: the six universal caps, cap precedence for gnotobiotic transfer, the Beta/Gamma/Delta boundary, the pre-registered scope-matched rule and its two declared alternatives, the independence record required for the Ζ subclaim, and the M/S/D artifact requirements. Cross-checked against the separately registered gut-microbiome-systemic-causality review to confirm neither borrows the other's evidence to clear a threshold. Validator re-run on the corrected score card and prose.

Findings

Rejected findings (checked, no change)

• Headline Γ. The case for Δ or higher is the one the review's own steelman makes: the THEMATIC hepatic-encephalopathy recurrence result is a randomized placebo-controlled human intervention with a clinical endpoint. Rejected: the recurrence contrast is a secondary endpoint whose pooled any-FMT comparison is post hoc, every participant already had cirrhosis and was on lactulose and rifaximin, and treating established disease does not test whether composition is the primary upstream cause. Under the pre-registered scope-matched rule the letter follows SC4, the only subclaim whose scope matches the registered broad-primacy claim.
• Scope-matched aggregation. Checked specifically against the known misreading. SC3 (Ε) is restricted to prespecified diagnoses under intervention and SC2 (Ζ) to rodents, so both are scope-restricted relative to a claim about primacy across human systemic and neurobehavioural disease; only SC4 matches, and both declared alternatives (weakest-link Β, primary-subclaim Γ) are correctly reported. The derivation's phrase "preregistered human-primacy gate" reads like primary-subclaim language, but the rule is declared as scope-matched in both artifacts and the two rules return the same letter here, so there is no rule-shopping and nothing to repair.
• The Ζ on SC2. Independence is recorded as the framework requires, naming three lines and the distinct systematic error each excludes — defined colonization under host-immune epistasis, non-lethal microbial enzyme inhibition in conventionally raised animals, and host intestinal-pathway interruption under matched community change. These do not share a failure mode. Checked, no change.
• Cap 5 cited for SC4 while the quoted rationale discusses diet, genotype and engraftment. Rejected: the cap-precedence paragraph states the binding inference explicitly — gnotobiotic transfer crosses the threshold for the rodent subclaim while cap 5 blocks the inference to endogenous human primacy — so the collision is resolved in writing rather than silently, which is what the framework requires.
• Multiple PMIDs printed as comma runs ("PMID24009397,24412651,36041436"). Rejected: used consistently throughout this document as its citation convention rather than as a sporadic rendering failure, and house style is outside the correction remit.
• "remains Gamma" spelled out in prose in the evidence section. Rejected: the normative descriptor rule governs the letter and descriptor fields, which are correct; "Gamma hard-rule audit" is a section label used across this corpus.
• Collective-author reference defect. No reference row carries a dropped consortium author or a leading comma. Checked, none found.
• Divergence recorded as "Contested" without rung arithmetic. Rejected: Contested is defined as the case where no single field-implied level applies.
• Overlap with the gut-microbiome-systemic-causality review. Eighteen PMIDs appear in both reference lists. Checked and rejected as a defect: the two reviews register different claims, each scores its own, and the shared records are used at the same scopes in both. Neither lets the recurrent C. difficile literature carry a systemic claim — this review names it an out-of-scope calibration comparator and the other scores it as an explicitly out-of-scope subclaim.

Residual limitations

Access depth is bounded: 8 of 67 records were read at partial-body depth and 59 at abstract/status depth, and several of the review's most load-bearing qualifications come from the partial-body readings — the diet under which the twin-transfer rescue fails, the antibiotic pretreatment asymmetry in the open-label hepatic-encephalopathy trial, and the unchanged HbA1c and baseline insulin imbalance in the pasteurized Akkermansia study. Those were not independently re-verified in this pass. The Γ on SC4 is a statement about broad upstream primacy only; the separately scored Ζ on rodent causality and Ε on bounded human contribution are not downgraded by it, and a reader who collapses the four subclaims into one letter will misread the review.

Approval: Following adversarial review and the corrections listed above, the revised document is approved. — Claude Opus 5.5 (Anthropic), 2026-10-14.

REFERENCES

1. Wang Z, Bergeron N, Levison BS et al. Impact of chronic dietary red meat, white meat, or non-meat protein on trimethylamine N-oxide metabolism and renal excretion in healthy men and women. European heart journal. 2019. PMID 30535398. DOI: 10.1093/eurheartj/ehy799. Access: abstract_metadata. Study: PMID30535398.

2. Depommier C, Everard A, Druart C et al. Supplementation with Akkermansia muciniphila in overweight and obese human volunteers: a proof-of-concept exploratory study. Nature medicine. 2019. PMID 31263284. DOI: 10.1038/s41591-019-0495-2. Access: full_text_partial. Study: PMID31263284.

3. Plovier H, Everard A, Druart C et al. A purified membrane protein from Akkermansia muciniphila or the pasteurized bacterium improves metabolism in obese and diabetic mice. Nature medicine. 2017. PMID 27892954. DOI: 10.1038/nm.4236. Access: abstract_metadata. Study: PMID27892954.

4. Bajaj JS, Fagan A, Gavis EA et al. Microbiota transplant for hepatic encephalopathy in cirrhosis: The THEMATIC trial. Journal of hepatology. 2025. PMID 39800192. DOI: 10.1016/j.jhep.2024.12.047. Access: abstract_metadata. Study: THEMATIC-NCT03796598.

5. Bajaj JS, Kassam Z, Fagan A et al. Fecal microbiota transplant from a rational stool donor improves hepatic encephalopathy: A randomized clinical trial. Hepatology (Baltimore, Md.). 2017. PMID 28586116. DOI: 10.1002/hep.29306. Access: full_text_partial. Study: PMID28586116.

6. Bajaj JS, Fagan A, Sterling RK et al. The multi-omic basis for hepatic encephalopathy recurrence: Analysis of the THEMATIC trial. JHEP reports : innovation in hepatology. 2026. PMID 41503571. DOI: 10.1016/j.jhepr.2025.101634. Access: abstract_metadata. Study: THEMATIC-NCT03796598.

7. Bajaj JS, Salzman NH, Acharya C et al. Fecal Microbial Transplant Capsules Are Safe in Hepatic Encephalopathy: A Phase 1, Randomized, Placebo-Controlled Trial. Hepatology (Baltimore, Md.). 2019. PMID 31038755. DOI: 10.1002/hep.30690. Access: abstract_metadata. Study: PMID31038755.

8. David LA, Maurice CF, Carmody RN et al. Diet rapidly and reproducibly alters the human gut microbiome. Nature. 2014. PMID 24336217. DOI: 10.1038/nature12820. Access: abstract_metadata. Study: PMID24336217.

9. Koh A, Molinaro A, Ståhlman M et al. Microbially Produced Imidazole Propionate Impairs Insulin Signaling through mTORC1. Cell. 2018. PMID 30401435. DOI: 10.1016/j.cell.2018.09.055. Access: abstract_metadata. Study: PMID30401435.

10. Ridaura VK, Faith JJ, Rey FE et al. Gut microbiota from twins discordant for obesity modulate metabolism in mice. Science (New York, N.Y.). 2013. PMID 24009397. DOI: 10.1126/science.1241214. Access: full_text_partial. Study: PMID24009397.

11. Turnbaugh PJ, Ley RE, Mahowald MA et al. An obesity-associated gut microbiome with increased capacity for energy harvest. Nature. 2006. PMID 17183312. DOI: 10.1038/nature05414. Access: abstract_metadata. Study: PMID17183312.

12. Wu H, Esteve E, Tremaroli V et al. Metformin alters the gut microbiome of individuals with treatment-naive type 2 diabetes, contributing to the therapeutic effects of the drug. Nature medicine. 2017. PMID 28530702. DOI: 10.1038/nm.4345. Access: abstract_metadata. Study: PMID28530702.

13. Ley RE, Bäckhed F, Turnbaugh P et al. Obesity alters gut microbial ecology. Proceedings of the National Academy of Sciences of the United States of America. 2005. PMID 16033867. DOI: 10.1073/pnas.0504978102. Access: abstract_metadata. Study: PMID16033867.

14. Meijnikman AS, Davids M, Herrema H et al. Microbiome-derived ethanol in nonalcoholic fatty liver disease. Nature medicine. 2022. PMID 36216942. DOI: 10.1038/s41591-022-02016-6. Access: abstract_metadata. Study: PMID36216942.

15. Andrikopoulos P, Aron-Wisnewsky J, Chakaroun R et al. Evidence of a causal and modifiable relationship between kidney function and circulating trimethylamine N-oxide. Nature communications. 2023. PMID 37730687. DOI: 10.1038/s41467-023-39824-4. Access: abstract_metadata. Study: PMID37730687.

16. De Vadder F, Kovatcheva-Datchary P, Goncalves D et al. Microbiota-generated metabolites promote metabolic benefits via gut-brain neural circuits. Cell. 2014. PMID 24412651. DOI: 10.1016/j.cell.2013.12.016. Access: abstract_metadata. Study: PMID24412651.

17. Velagapudi VR, Hezaveh R, Reigstad CS et al. The gut microbiota modulates host energy and lipid metabolism in mice. Journal of lipid research. 2010. PMID 20040631. DOI: 10.1194/jlr.M002774. Access: abstract_metadata. Study: PMID20040631.

18. Maini Rekdal V, Bess EN, Bisanz JE et al. Discovery and inhibition of an interspecies gut bacterial pathway for Levodopa metabolism. Science (New York, N.Y.). 2019. PMID 31196984. DOI: 10.1126/science.aau6323. Access: abstract_metadata. Study: PMID31196984.

19. Sampson TR, Debelius JW, Thron T et al. Gut Microbiota Regulate Motor Deficits and Neuroinflammation in a Model of Parkinson's Disease. Cell. 2016. PMID 27912057. DOI: 10.1016/j.cell.2016.11.018. Access: full_text_partial. Study: PMID27912057.

20. Yano JM, Yu K, Donaldson GP et al. Indigenous bacteria from the gut microbiota regulate host serotonin biosynthesis. Cell. 2015. PMID 25860609. DOI: 10.1016/j.cell.2015.02.047. Access: abstract_metadata. Study: PMID25860609.

21. Hsiao EY, McBride SW, Hsien S et al. Microbiota modulate behavioral and physiological abnormalities associated with neurodevelopmental disorders. Cell. 2013. PMID 24315484. DOI: 10.1016/j.cell.2013.11.024. Access: full_text_partial. Study: PMID24315484.

22. Sharon G, Cruz NJ, Kang DW et al. Human Gut Microbiota from Autism Spectrum Disorder Promote Behavioral Symptoms in Mice. Cell. 2019. PMID 31150625. DOI: 10.1016/j.cell.2019.05.004. Access: full_text_partial. Study: PMID31150625.

23. Wu WL, Adame MD, Liou CW et al. Microbiota regulate social behaviour via stress response neurons in the brain. Nature. 2021. PMID 34194038. DOI: 10.1038/s41586-021-03669-y. Access: abstract_metadata. Study: PMID34194038.

24. Olson CA, Vuong HE, Yano JM et al. The Gut Microbiota Mediates the Anti-Seizure Effects of the Ketogenic Diet. Cell. 2018. PMID 29804833. DOI: 10.1016/j.cell.2018.04.027. Access: abstract_metadata. Study: PMID29804833.

25. Vuong HE, Pronovost GN, Williams DW et al. The maternal microbiome modulates fetal neurodevelopment in mice. Nature. 2020. PMID 32968276. DOI: 10.1038/s41586-020-2745-3. Access: abstract_metadata. Study: PMID32968276.

26. Wallen ZD, Demirkan A, Twa G et al. Metagenomics of Parkinson's disease implicates the gut microbiome in multiple disease mechanisms. Nature communications. 2022. PMID 36376318. DOI: 10.1038/s41467-022-34667-x. Access: abstract_metadata. Study: PMID36376318.

27. Falony G, Joossens M, Vieira-Silva S et al. Population-level analysis of gut microbiome variation. Science (New York, N.Y.). 2016. PMID 27126039. DOI: 10.1126/science.aad3503. Access: abstract_metadata. Study: FGFP-and-LifeLines-DEEP-shared-component.

28. Bartolomaeus TUP, Birkner T, Bartolomaeus H et al. Quantifying technical confounders in microbiome studies. Cardiovascular research. 2021. PMID 32374853. DOI: 10.1093/cvr/cvaa128. Access: abstract_metadata. Study: PMID32374853.

29. Qin J, Li Y, Cai Z et al. A metagenome-wide association study of gut microbiota in type 2 diabetes. Nature. 2012. PMID 23023125. DOI: 10.1038/nature11450. Access: abstract_metadata. Study: T2D-metagenomes-reanalysed-in-Forslund.

30. Forslund K, Hildebrand F, Nielsen T et al. Disentangling type 2 diabetes and metformin treatment signatures in the human gut microbiota. Nature. 2015. PMID 26633628. DOI: 10.1038/nature15766. Access: full_text_partial. Study: Forslund-pooled-T2D-metagenomes.

31. Vandeputte D, Kathagen G, D'hoe K et al. Quantitative microbiome profiling links gut community variation to microbial load. Nature. 2017. PMID 29143816. DOI: 10.1038/nature24460. Access: abstract_metadata. Study: PMID29143816.

32. Kurilshikov A, Medina-Gomez C, Bacigalupe R et al. Large-scale association analyses identify host factors influencing human gut microbiome composition. Nature genetics. 2021. PMID 33462485. DOI: 10.1038/s41588-020-00763-1. Access: abstract_metadata. Study: PMID33462485.

33. Valles-Colomer M, Falony G, Darzi Y et al. The neuroactive potential of the human gut microbiota in quality of life and depression. Nature microbiology. 2019. PMID 30718848. DOI: 10.1038/s41564-018-0337-x. Access: abstract_metadata. Study: PMID30718848.

34. Duscha A, Gisevius B, Hirschberg S et al. Propionic Acid Shapes the Multiple Sclerosis Disease Course by an Immunomodulatory Mechanism. Cell. 2020. PMID 32160527. DOI: 10.1016/j.cell.2020.02.035. Access: abstract_metadata. Study: PMID32160527.

35. Zhernakova A, Kurilshikov A, Bonder MJ et al. Population-based metagenomics analysis reveals markers for gut microbiome composition and diversity. Science (New York, N.Y.). 2016. PMID 27126040. DOI: 10.1126/science.aad3369. Access: abstract_metadata. Study: LifeLines-DEEP-shared-component.

36. Le Chatelier E, Nielsen T, Qin J et al. Richness of human gut microbiome correlates with metabolic markers. Nature. 2013. PMID 23985870. DOI: 10.1038/nature12506. Access: abstract_metadata. Study: PMID23985870.

37. Zhu W, Gregory JC, Org E et al. Gut Microbial Metabolite TMAO Enhances Platelet Hyperreactivity and Thrombosis Risk. Cell. 2016. PMID 26972052. DOI: 10.1016/j.cell.2016.02.011. Access: abstract_metadata. Study: Hazen-angiography-shared-component.

38. Wang Z, Roberts AB, Buffa JA et al. Non-lethal Inhibition of Gut Microbial Trimethylamine Production for the Treatment of Atherosclerosis. Cell. 2015. PMID 26687352. DOI: 10.1016/j.cell.2015.11.055. Access: abstract_metadata. Study: PMID26687352.

39. Jie Z, Xia H, Zhong SL et al. The gut microbiome in atherosclerotic cardiovascular disease. Nature communications. 2017. PMID 29018189. DOI: 10.1038/s41467-017-00900-1. Access: abstract_metadata. Study: PMID29018189.

40. Tang WH, Wang Z, Levison BS et al. Intestinal microbial metabolism of phosphatidylcholine and cardiovascular risk. The New England journal of medicine. 2013. PMID 23614584. DOI: 10.1056/NEJMoa1109400. Access: abstract_metadata. Study: Hazen-angiography-4007-shared-component.

41. Koeth RA, Wang Z, Levison BS et al. Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis. Nature medicine. 2013. PMID 23563705. DOI: 10.1038/nm.3145. Access: abstract_metadata. Study: PMID23563705.

42. Kawano Y, Edwards M, Huang Y et al. Microbiota imbalance induced by dietary sugar disrupts immune-mediated protection from metabolic syndrome. Cell. 2022. PMID 36041436. DOI: 10.1016/j.cell.2022.08.005. Access: abstract_metadata. Study: PMID36041436.

43. Atarashi K, Tanoue T, Shima T et al. Induction of colonic regulatory T cells by indigenous Clostridium species. Science (New York, N.Y.). 2011. PMID 21205640. DOI: 10.1126/science.1198469. Access: abstract_metadata. Study: PMID21205640.

44. Katz Sand I, Zhu Y, Ntranos A et al. Disease-modifying therapies alter gut microbial composition in MS. Neurology(R) neuroimmunology & neuroinflammation. 2019. PMID 30568995. DOI: 10.1212/NXI.0000000000000517. Access: abstract_metadata. Study: PMID30568995.

45. Ivanov II, Atarashi K, Manel N et al. Induction of intestinal Th17 cells by segmented filamentous bacteria. Cell. 2009. PMID 19836068. DOI: 10.1016/j.cell.2009.09.033. Access: abstract_metadata. Study: PMID19836068.

46. Cekanaviciute E, Yoo BB, Runia TF et al. Gut bacteria from multiple sclerosis patients modulate human T cells and exacerbate symptoms in mouse models. Proceedings of the National Academy of Sciences of the United States of America. 2017. PMID 28893978. DOI: 10.1073/pnas.1711235114. Access: abstract_metadata. Study: PMID28893978.

47. Scheperjans F, Levo R, Bosch B et al. Fecal Microbiota Transplantation for Treatment of Parkinson Disease: A Randomized Clinical Trial. JAMA neurology. 2024. PMID 39073834. DOI: 10.1001/jamaneurol.2024.2305. Access: abstract_metadata. Study: PMID39073834.

48. Feng R, Zhu Q, Wang A et al. Effect of fecal microbiota transplantation on patients with sporadic amyotrophic lateral sclerosis: a randomized, double-blind, placebo-controlled trial. BMC medicine. 2024. PMID 39617896. DOI: 10.1186/s12916-024-03781-6. Access: abstract_metadata. Study: PMID39617896.

49. Cheng Y, Tan G, Zhu Q et al. Efficacy of fecal microbiota transplantation in patients with Parkinson's disease: clinical trial results from a randomized, placebo-controlled design. Gut microbes. 2023. PMID 38057970. DOI: 10.1080/19490976.2023.2284247. Access: abstract_metadata. Study: PMID38057970.

50. Mazzone L, Dooling SW, Volpe E et al. Precision microbial intervention improves social behavior but not autism severity: A pilot double-blind randomized placebo-controlled trial. Cell host & microbe. 2024. PMID 38113884. DOI: 10.1016/j.chom.2023.11.021. Access: abstract_metadata. Study: PMID38113884.

51. Wang J, Xue L, Zhang M et al. Colonoscopic fecal microbiota transplantation for Mild-to-Moderate Parkinson's Disease: A randomized controlled trial. Brain, behavior, and immunity. 2025. PMID 40848995. DOI: 10.1016/j.bbi.2025.106086. Access: abstract_metadata. Study: PMID40848995.

52. Bruggeman A, Vandendriessche C, Hamerlinck H et al. Safety and efficacy of faecal microbiota transplantation in patients with mild to moderate Parkinson's disease (GUT-PARFECT): a double-blind, placebo-controlled, randomised, phase 2 trial. EClinicalMedicine. 2024. PMID 38686220. DOI: 10.1016/j.eclinm.2024.102563. Access: full_text_partial. Study: PMID38686220.

53. Kelly JR, Borre Y, O' Brien C et al. Transferring the blues: Depression-associated gut microbiota induces neurobehavioural changes in the rat. Journal of psychiatric research. 2016. PMID 27491067. DOI: 10.1016/j.jpsychires.2016.07.019. Access: abstract_metadata. Study: PMID27491067.

54. Zheng P, Zeng B, Zhou C et al. Gut microbiome remodeling induces depressive-like behaviors through a pathway mediated by the host's metabolism. Molecular psychiatry. 2016. PMID 27067014. DOI: 10.1038/mp.2016.44. Access: abstract_metadata. Study: PMID27067014.

55. Kelly JR, Allen AP, Temko A et al. Lost in translation? The potential psychobiotic Lactobacillus rhamnosus (JB-1) fails to modulate stress or cognitive performance in healthy male subjects. Brain, behavior, and immunity. 2017. PMID 27865949. DOI: 10.1016/j.bbi.2016.11.018. Access: abstract_metadata. Study: PMID27865949.

56. Vrieze A, Van Nood E, Holleman F et al. Transfer of intestinal microbiota from lean donors increases insulin sensitivity in individuals with metabolic syndrome. Gastroenterology. 2012. PMID 22728514. DOI: 10.1053/j.gastro.2012.06.031. Access: abstract_metadata. Study: PMID22728514.

57. Vrieze A, Out C, Fuentes S et al. Impact of oral vancomycin on gut microbiota, bile acid metabolism, and insulin sensitivity. Journal of hepatology. 2014. PMID 24316517. DOI: 10.1016/j.jhep.2013.11.034. Access: abstract_metadata. Study: PMID24316517.

58. Reijnders D, Goossens GH, Hermes GD et al. Effects of Gut Microbiota Manipulation by Antibiotics on Host Metabolism in Obese Humans: A Randomized Double-Blind Placebo-Controlled Trial. Cell metabolism. 2016. PMID 27411009. DOI: 10.1016/j.cmet.2016.06.016. Access: abstract_metadata. Study: PMID27411009.

59. Kootte RS, Levin E, Salojärvi J et al. Improvement of Insulin Sensitivity after Lean Donor Feces in Metabolic Syndrome Is Driven by Baseline Intestinal Microbiota Composition. Cell metabolism. 2017. PMID 28978426. DOI: 10.1016/j.cmet.2017.09.008. Access: abstract_metadata. Study: PMID28978426.

60. Smits LP, Kootte RS, Levin E et al. Effect of Vegan Fecal Microbiota Transplantation on Carnitine- and Choline-Derived Trimethylamine-N-Oxide Production and Vascular Inflammation in Patients With Metabolic Syndrome. Journal of the American Heart Association. 2018. PMID 29581220. DOI: 10.1161/JAHA.117.008342. Access: abstract_metadata. Study: PMID29581220.

61. Yu EW, Gao L, Stastka P et al. Fecal microbiota transplantation for the improvement of metabolism in obesity: The FMT-TRIM double-blind placebo-controlled pilot trial. PLoS medicine. 2020. PMID 32150549. DOI: 10.1371/journal.pmed.1003051. Access: abstract_metadata. Study: PMID32150549.

62. Yap CX, Henders AK, Alvares GA et al. Autism-related dietary preferences mediate autism-gut microbiome associations. Cell. 2021. PMID 34767757. DOI: 10.1016/j.cell.2021.10.015. Access: abstract_metadata. Study: PMID34767757.

63. Vandeputte D, Falony G, Vieira-Silva S et al. Stool consistency is strongly associated with gut microbiota richness and composition, enterotypes and bacterial growth rates. Gut. 2016. PMID 26069274. DOI: 10.1136/gutjnl-2015-309618. Access: abstract_metadata. Study: PMID26069274.

64. Berer K, Gerdes LA, Cekanaviciute E et al. Gut microbiota from multiple sclerosis patients enables spontaneous autoimmune encephalomyelitis in mice. Proceedings of the National Academy of Sciences of the United States of America. 2017. PMID 28893994. DOI: 10.1073/pnas.1711233114. Access: abstract_metadata. Study: PMID28893994.

65. Berer K, Mues M, Koutrolos M et al. Commensal microbiota and myelin autoantigen cooperate to trigger autoimmune demyelination. Nature. 2011. PMID 22031325. DOI: 10.1038/nature10554. Access: abstract_metadata. Study: PMID22031325.

66. Wang Z, Klipfell E, Bennett BJ et al. Gut flora metabolism of phosphatidylcholine promotes cardiovascular disease. Nature. 2011. PMID 21475195. DOI: 10.1038/nature09922. Access: abstract_metadata. Study: PMID21475195.

67. Wu HJ, Ivanov II, Darce J et al. Gut-residing segmented filamentous bacteria drive autoimmune arthritis via T helper 17 cells. Immunity. 2010. PMID 20620945. DOI: 10.1016/j.immuni.2010.06.001. Access: abstract_metadata. Study: PMID20620945.

Source-specific evidence cards

[1] Impact of chronic dietary red meat, white meat, or non-meat protein on trimethylamine N-oxide metabolism and renal excretion in healthy men and women.

Shows: Controlled dietary crossover changes TMAO production and renal excretion; withdrawal reduces circulating TMAO.

Does not show: Diet and kidney handling determine the readout; no cardiovascular disease prevention endpoint.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[2] Supplementation with Akkermansia muciniphila in overweight and obese human volunteers: a proof-of-concept exploratory study.

Shows: Placebo-controlled pasteurized Akkermansia supplementation improves insulin sensitivity and circulating lipids in insulin-resistant overweight adults.

Does not show: HOMA-based indices, baseline insulin imbalance, small exploratory sample and unchanged HbA1c/overall community structure restrict inference; weight/fat changes are not significant.

Access/status: Complete primary abstract and linked-status metadata examined. Selected body sections: 2:Main text:paragraph1, 2:Main text:paragraph3, 2:Main text:paragraph5, 2:Main text:paragraph12, 2:Main text:paragraph13, 2:Main text:paragraph14. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[3] A purified membrane protein from Akkermansia muciniphila or the pasteurized bacterium improves metabolism in obese and diabetic mice.

Shows: Pasteurized Akkermansia and its outer-membrane protein partly reproduce metabolic benefits in obese/diabetic mice.

Does not show: Administration demonstrates bounded sufficiency and host-receptor plausibility, not endogenous necessity or human disease prevention.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC3.

[4] Microbiota transplant for hepatic encephalopathy in cirrhosis: The THEMATIC trial.

Shows: THEMATIC compares placebo with capsule/enema FMT in treated cirrhosis and reports lower HE recurrence in a post hoc any-FMT comparison.

Does not show: Safety is primary; recurrence is secondary and its pooled contrast post hoc. Underlying cirrhosis and concurrent drugs remain upstream.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[5] Fecal microbiota transplant from a rational stool donor improves hepatic encephalopathy: A randomized clinical trial.

Shows: Randomized open-label FMT with antibiotic pretreatment improves cognition and recurrent HE compared with standard care.

Does not show: Small male cohort and unmatched antibiotic pretreatment; crude donor community does not identify the microbial causal factor.

Access/status: Complete primary abstract and linked-status metadata examined. Selected body sections: 0:EXPERIMENTAL PROCEDURES:paragraph1, 0:EXPERIMENTAL PROCEDURES:paragraph4, 2:RESULTS::paragraph0, 2:RESULTS::paragraph1, 2:RESULTS::paragraph3, 2:RESULTS::paragraph4. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[6] The multi-omic basis for hepatic encephalopathy recurrence: Analysis of the THEMATIC trial.

Shows: THEMATIC secondary multi-omics links HE recurrence with microbial, metabolite and inflammatory signatures.

Does not show: Same trial as PMID39800192; outcome-selected molecular associations are not new causal lines or proof of individual taxa necessity.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC3, SC4.

[7] Fecal Microbial Transplant Capsules Are Safe in Hepatic Encephalopathy: A Phase 1, Randomized, Placebo-Controlled Trial.

Shows: Placebo-controlled FMT capsules improve cognitive testing and mucosal measures without antibiotic pretreatment in cirrhosis.

Does not show: Phase1 safety focus; infection/HE episodes are similar and efficacy remains provisional. Linked erratum is attached and not separately counted.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. Erratum in: PMID33464567. Subclaims: SC3, SC4.

[8] Diet rapidly and reproducibly alters the human gut microbiome.

Shows: Short-term animal versus plant diets rapidly change microbial structure and activity.

Does not show: Shows diet-to-microbiome direction rather than proving microbes irrelevant to downstream disease.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC4.

[9] Microbially Produced Imidazole Propionate Impairs Insulin Signaling through mTORC1.

Shows: Microbial imidazole propionate impairs mouse glucose tolerance and activates a p38gamma-p62-mTORC1 signaling route.

Does not show: Administered metabolite and human associations do not establish endogenous human contribution or broad compositional primacy.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC2, SC4.

[10] Gut microbiota from twins discordant for obesity modulate metabolism in mice.

Shows: Discordant-twin communities and culture collections transmit body-fat phenotypes; lean-community cohousing rescue depends on diet.

Does not show: Rescue fails on high-saturated-fat/low-fruit-vegetable diet. Early glucose contrast does not establish full insulin resistance; transfer remains recipient-mouse causality.

Access/status: Complete primary abstract and linked-status metadata examined. Selected body sections: 3:Phenotypes produced by bacterial culture collections, 7:Diet-specific effects. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

[11] An obesity-associated gut microbiome with increased capacity for energy harvest.

Shows: Obese-donor mouse microbiota increases energy-harvest potential and fat gain in germ-free recipients.

Does not show: Crude transfer and genetically obese donors do not isolate strains or establish general human obesity primacy.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

[12] Metformin alters the gut microbiome of individuals with treatment-naive type 2 diabetes, contributing to the therapeutic effects of the drug.

Shows: Randomized metformin changes human microbiota; post-treatment donor microbiota improves glucose tolerance after mouse transfer.

Does not show: Drug has host effects; recipient transfer supports a contribution but does not measure microbiome-specific mediation of human glycemic benefit.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC3, SC4.

[13] Obesity alters gut microbial ecology.

Shows: Leptin-deficient obese mice differ in broad bacterial divisions from related lean mice on the same diet.

Does not show: Genetic host phenotype can reshape ecology; division-level signatures are not a causal mechanism.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[14] Microbiome-derived ethanol in nonalcoholic fatty liver disease.

Shows: Portal sampling and ADH inhibition reveal microbial ethanol production in NAFLD, abolished after antibiotics.

Does not show: Intervention changes an exposure biomarker; no demonstrated liver disease trajectory change or strain-specific causality.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[15] Evidence of a causal and modifiable relationship between kidney function and circulating trimethylamine N-oxide.

Shows: Kidney function predicts circulating TMAO more strongly than diet/community composition; mouse exposure supports bidirectional renal injury.

Does not show: Mediation and propensity matching are not randomized human mechanism tests; concentration alone cannot identify microbial primacy.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC2, SC4.

[16] Microbiota-generated metabolites promote metabolic benefits via gut-brain neural circuits.

Shows: SCFA/fiber metabolic benefits disappear in intestinal-gluconeogenesis-deficient mice despite similar microbiota changes.

Does not show: Host pathway dependence and administered metabolites establish conditional benefit; endogenous strain necessity remains unspecified.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

[17] The gut microbiota modulates host energy and lipid metabolism in mice.

Shows: Germ-free versus conventionally raised mice differ in energy metabolites and tissue lipid distributions.

Does not show: Developmental/immune differences accompany germ-free status; molecular profiles do not establish a disease phenotype.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2.

[18] Discovery and inhibition of an interspecies gut bacterial pathway for Levodopa metabolism.

Shows: Defined bacterial enzymes metabolize levodopa and pathway inhibition raises mouse drug bioavailability.

Does not show: Functional pharmacokinetic effect is distinct from initiating Parkinson disease or changing neurodegeneration.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

[19] Gut Microbiota Regulate Motor Deficits and Neuroinflammation in a Model of Parkinson's Disease.

Shows: Microbial depletion/recolonization and SCFA challenge change motor deficits and microglia in alpha-synuclein-overexpressing mice.

Does not show: Host transgene establishes vulnerability; forced human-donor transfer cannot show endogenous human PD primacy.

Access/status: Complete primary abstract and linked-status metadata examined. Selected body sections: 1:Results:paragraph0, 1:Results:paragraph5, 1:Results:paragraph8, 1:Results:paragraph12. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

[20] Indigenous bacteria from the gut microbiota regulate host serotonin biosynthesis.

Shows: Spore-forming bacteria regulate host peripheral serotonin, GI motility and platelet function.

Does not show: Peripheral serotonin is not demonstrated brain neurotransmission; linked erratum with no PMID supplied remains explicit.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. Erratum in: PMID not supplied. Subclaims: SC2, SC4.

[21] Microbiota modulate behavioral and physiological abnormalities associated with neurodevelopmental disorders.

Shows: Bacteroides fragilis improves gut permeability and selected behaviors after maternal immune activation; a metabolite challenge induces some abnormalities.

Does not show: Social deficits persist; 4EPS induces anxiety/startle changes but not repetitive or communicative deficits. Maternal immune activation is upstream and human ASD causality is untested.

Access/status: Complete primary abstract and linked-status metadata examined. Selected body sections: 5:B. fragilis Treatment Corrects ASD-Related Behavioral Abnormalities, 7:B. fragilis Treatment Corrects Levels of MIA-Induced Serum Metabolites, 8:A Serum Metabolite Induces ASD-Related Behavior. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

[22] Human Gut Microbiota from Autism Spectrum Disorder Promote Behavioral Symptoms in Mice.

Shows: Human ASD-donor microbiota induces altered mouse behavior and splicing; candidate metabolites improve a mouse model.

Does not show: Donor, sex and age affect recipient behavior. High-dose taurine/5AV rescue depends on prenatal/weaning exposure; juvenile-only treatment fails in BTBR. Mouse phenotype is distinct from human ASD initiation.

Access/status: Complete primary abstract and linked-status metadata examined. Selected body sections: 1:RESULTS:paragraph1, 1:RESULTS:paragraph12, 1:RESULTS:paragraph13, 1:RESULTS:paragraph14, 3:STAR Methods:paragraph28, 3:STAR Methods:paragraph29, 3:STAR Methods:paragraph38. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

[23] Microbiota regulate social behaviour via stress response neurons in the brain.

Shows: Microbial depletion changes male mouse social behavior; host HPA/neuronal interruption and Enterococcus faecalis reverse defined defects.

Does not show: Circuit specificity is conditional on stress and depletion; mouse social activity is not a human disease endpoint.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

[24] The Gut Microbiota Mediates the Anti-Seizure Effects of the Ketogenic Diet.

Shows: Defined Akkermansia/Parabacteroides colonization restores ketogenic-diet seizure protection and transfers protection under control diet.

Does not show: Two mouse seizure contexts support treatment mediation, not universal epilepsy causation. Linked erratum remains attached.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. Erratum in: PMID30007420. Subclaims: SC2, SC4.

[25] The maternal microbiome modulates fetal neurodevelopment in mice.

Shows: Maternal microbial depletion impairs fetal thalamocortical axons; defined consortium/metabolites rescue and alter later tactile behavior.

Does not show: Prenatal physiological development and specific behavioral tasks do not demonstrate human neurodevelopmental disease primacy.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

[26] Metagenomics of Parkinson's disease implicates the gut microbiome in multiple disease mechanisms.

Shows: Deep metagenomics identifies broad PD-associated species, genes and pathway shifts.

Does not show: Calling predicted pathways disease permissive does not demonstrate human causal dependency; medication, transit and disease remain alternatives.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[27] Population-level analysis of gut microbiome variation.

Shows: Population cohorts identify stool consistency and medication as major microbiome covariates.

Does not show: Covariate association warns about confounding but does not prove all disease associations disappear.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[28] Quantifying technical confounders in microbiome studies.

Shows: Comparative sample-processing experiments show extraction methods can mimic biological microbiome differences.

Does not show: Technical measurement artifact is not a direct test of disease mechanism.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[29] A metagenome-wide association study of gut microbiota in type 2 diabetes.

Shows: Two-stage human metagenomics identifies diabetes-associated microbial markers and functions.

Does not show: Diagnostic classification and abundance association do not establish direction or microbial necessity.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[30] Disentangling type 2 diabetes and metformin treatment signatures in the human gut microbiota.

Shows: Medication-stratified metagenomics separates metformin-associated features from untreated diabetes signatures.

Does not show: Residual untreated-disease association remains; inferred therapeutic mediation is not isolated by human intervention. Linked erratum is retained.

Access/status: Complete primary abstract and linked-status metadata examined. Selected body sections: 3:Main text:paragraph0, 3:Main text:paragraph2, 3:Main text:paragraph4, 3:Main text:paragraph5, 3:Main text:paragraph6. No complete-paper or supplement audit claimed. Erratum in: PMID28470190. Subclaims: SC1, SC4.

[31] Quantitative microbiome profiling links gut community variation to microbial load.

Shows: Flow-cytometry plus sequencing reveals variable microbial loads and compositional artifacts of relative profiling.

Does not show: Counts improve measurement; they do not determine whether a disease signature is causal.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[32] Large-scale association analyses identify host factors influencing human gut microbiome composition.

Shows: MiBioGen links host loci with taxa and reports suggestive MR disease relationships.

Does not show: Low taxonomic instrument coverage, dietary pathways and pleiotropy constrain a broad human causal-primacy inference.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[33] The neuroactive potential of the human gut microbiota in quality of life and depression.

Shows: Replicated population microbiome features correlate with depression and quality of life after antidepressant adjustment.

Does not show: Neuroactive pathway potential and adjusted association do not establish microbial brain activity or human disease causation.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[34] Propionic Acid Shapes the Multiple Sclerosis Disease Course by an Immunomodulatory Mechanism.

Shows: Propionate supplementation changes Treg function; post hoc long-term analyses associate supplementation with improved MS course.

Does not show: Nonrandomized proof-of-concept/add-on treatment and post hoc endpoints do not isolate microbial source or clinical causal effect.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[35] Population-based metagenomics analysis reveals markers for gut microbiome composition and diversity.

Shows: Dutch population metagenomics links community variation with diet, drugs and intrinsic host factors.

Does not show: Shares LifeLines-DEEP material with PMID27126039; not an independent replication line.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[36] Richness of human gut microbiome correlates with metabolic markers.

Shows: Low microbial gene richness tracks adiposity, metabolic abnormalities and later weight gain.

Does not show: Prospective weight association still permits diet, medication and host-state causes.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[37] Gut Microbial Metabolite TMAO Enhances Platelet Hyperreactivity and Thrombosis Risk.

Shows: Diet/TMAO exposure and microbial transfer affect platelet reactivity and experimental thrombosis, paired with human event prediction.

Does not show: Human event risk is observational; overlapping angiography/platform material and administered metabolite are not independent clinical causality.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC3, SC4.

[38] Non-lethal Inhibition of Gut Microbial Trimethylamine Production for the Treatment of Atherosclerosis.

Shows: DMB inhibits microbial TMA generation and decreases diet-enhanced atherosclerotic lesions in ApoE-deficient mice.

Does not show: Chemical specificity and selected diet/genotype need controls; no human hard-endpoint trial establishes broad primacy.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

[39] The gut microbiome in atherosclerotic cardiovascular disease.

Shows: Human ACVD metagenomics identifies taxa and functions associated with disease after drug analyses.

Does not show: Case-control disease status remains susceptible to reverse causation and residual confounding.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[40] Intestinal microbial metabolism of phosphatidylcholine and cardiovascular risk.

Shows: Antibiotics suppress isotope-labeled choline-derived TMAO with recovery after withdrawal; higher TMAO predicts cardiovascular events.

Does not show: Production causality is established; cardiovascular disease causality is not tested by the biomarker intervention.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[41] Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis.

Shows: Carnitine feeding increases microbial TMAO and mouse atherosclerosis, attenuated by microbial suppression; human challenge is diet-dependent.

Does not show: Broad antibiotics and administered substrates do not isolate endogenous human cardiovascular dependency.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC3, SC4.

[42] Microbiota imbalance induced by dietary sugar disrupts immune-mediated protection from metabolic syndrome.

Shows: Dietary sugar displaces Th17-inducing microbes; microbial/immune restoration protects against mouse metabolic syndrome.

Does not show: Diet, microbes and host immunity interact; no autonomous microbial initiator or general human implication is established.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

[43] Induction of colonic regulatory T cells by indigenous Clostridium species.

Shows: Defined Clostridium strains induce colonic Tregs and protect against experimental colitis and systemic IgE responses.

Does not show: Selected mouse immune contexts do not establish primary human autoimmune disease causes.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2.

[44] Disease-modifying therapies alter gut microbial composition in MS.

Shows: MS disease-modifying treatment groups have distinct microbial composition and predicted functions.

Does not show: Treatment is not randomized here; warns about medication effects without proving microbial irrelevance.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[45] Induction of intestinal Th17 cells by segmented filamentous bacteria.

Shows: Single segmented filamentous bacterium induces mucosal Th17 cells and pathogen resistance.

Does not show: Mucosal physiology is distinct from systemic disease initiation; disease relevance is tested separately.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2.

[46] Gut bacteria from multiple sclerosis patients modulate human T cells and exacerbate symptoms in mouse models.

Shows: MS-associated strains alter T-cell responses and patient-donor transfer exacerbates induced mouse autoimmune encephalomyelitis.

Does not show: Challenge-induced recipient disease and ex vivo human cells do not establish human MS initiation. Linked erratum attached.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. Erratum in: PMID29073033. Subclaims: SC1, SC2, SC4.

[47] Fecal Microbiota Transplantation for Treatment of Parkinson Disease: A Randomized Clinical Trial.

Shows: Placebo-controlled PD FMT trial finds no primary clinical benefit despite stronger donor-dependent microbiota changes.

Does not show: Negative regimen-specific test is not a positive threshold crossing and does not exclude every strain or intervention.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[48] Effect of fecal microbiota transplantation on patients with sporadic amyotrophic lateral sclerosis: a randomized, double-blind, placebo-controlled trial.

Shows: Placebo-controlled sporadic ALS FMT changes community features without slowing ALSFRS-R decline.

Does not show: Small trial cannot exclude modest effects; constipation or mood improvements do not establish neurodegeneration modification.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[49] Efficacy of fecal microbiota transplantation in patients with Parkinson's disease: clinical trial results from a randomized, placebo-controlled design.

Shows: Randomized PD oral FMT reports improved symptom scores and GI measures compared with placebo.

Does not show: Small trial and medication interactions require replication; symptomatic change is distinct from disease initiation or neuron preservation.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[50] Precision microbial intervention improves social behavior but not autism severity: A pilot double-blind randomized placebo-controlled trial.

Shows: Defined L. reuteri combination improves social functioning in ASD while overall autism severity and community composition do not change.

Does not show: Pilot selected-domain benefit does not establish overall ASD treatment, microbial-composition primacy or strain-specific human efficacy.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[51] Colonoscopic fecal microbiota transplantation for Mild-to-Moderate Parkinson's Disease: A randomized controlled trial.

Shows: Small blinded fresh-colonoscopic FMT trial reports improved PD motor, nonmotor and constipation scores over short follow-up.

Does not show: Multiple symptom measures and small single-center sample do not establish neuroprotection or broad microbial primacy.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[52] Safety and efficacy of faecal microbiota transplantation in patients with mild to moderate Parkinson's disease (GUT-PARFECT): a double-blind, placebo-controlled, randomised, phase 2 trial.

Shows: GUT-PARFECT compares donor with autologous FMT and reports mild off-medication motor benefit over twelve months.

Does not show: Small stage-defined cohort, baseline imbalance and comparator effects constrain generalization; symptomatic benefit is not neuron-preservation proof.

Access/status: Complete primary abstract and linked-status metadata examined. Selected body sections: 1:Methods:paragraph3, 1:Methods:paragraph9, 1:Methods:paragraph11, 2:Results:paragraph2, 2:Results:paragraph5, 2:Results:paragraph12. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[53] Transferring the blues: Depression-associated gut microbiota induces neurobehavioural changes in the rat.

Shows: Depression-donor communities induce anhedonia/anxiety-like behavior and altered tryptophan metabolism in depleted rats.

Does not show: Recipient behavior is not human depressive illness; crude community transfer leaves diet/drug and strain identity unresolved.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC2, SC4.

[54] Gut microbiome remodeling induces depressive-like behaviors through a pathway mediated by the host's metabolism.

Shows: MDD-donor microbiota induces mouse depression-like behavior with metabolic changes.

Does not show: Germ-free recipient physiology and donor confounding restrict inference to human disease primacy.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC2, SC4.

[55] Lost in translation? The potential psychobiotic Lactobacillus rhamnosus (JB-1) fails to modulate stress or cognitive performance in healthy male subjects.

Shows: Randomized JB-1 crossover finds no stress, cognitive, inflammatory or HPA benefit in healthy men.

Does not show: Healthy men are a translational comparator, not a disease-cohort test; null does not exclude effects in prospectively defined disorders.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[56] Transfer of intestinal microbiota from lean donors increases insulin sensitivity in individuals with metabolic syndrome.

Shows: Randomized lean-donor versus autologous FMT improves short-term clamp insulin sensitivity in metabolic syndrome.

Does not show: Small short-term physiology endpoint does not show durable prevention, strain identity or broad primacy. Linked erratum without supplied PMID retained.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. Erratum in: PMID not supplied. Subclaims: SC3, SC4.

[57] Impact of oral vancomycin on gut microbiota, bile acid metabolism, and insulin sensitivity.

Shows: Randomized vancomycin versus amoxicillin changes microbiota/bile acids and lowers clamp insulin sensitivity.

Does not show: No placebo and broad drug actions constrain microbial specificity; not a hard disease-trajectory endpoint.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[58] Effects of Gut Microbiota Manipulation by Antibiotics on Host Metabolism in Obese Humans: A Randomized Double-Blind Placebo-Controlled Trial.

Shows: Placebo-controlled antibiotics substantially alter microbiota/metabolites without changing measured metabolic health or later insulin sensitivity.

Does not show: Regimen-specific null despite community change; no claim that every microbial factor is dispensable. Search-linked erratum is attached.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. Erratum in: PMID27508877. Subclaims: SC3, SC4.

[59] Improvement of Insulin Sensitivity after Lean Donor Feces in Metabolic Syndrome Is Driven by Baseline Intestinal Microbiota Composition.

Shows: Lean-donor FMT improves insulin sensitivity at six weeks but not eighteen weeks; baseline composition predicts response.

Does not show: Predictor must be validated prospectively; responders cannot define the claimed scope after outcomes.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[60] Effect of Vegan Fecal Microbiota Transplantation on Carnitine- and Choline-Derived Trimethylamine-N-Oxide Production and Vascular Inflammation in Patients With Metabolic Syndrome.

Shows: Vegan-donor FMT changes community toward donor profile in some recipients without changing TMAO production or vascular-inflammation measures.

Does not show: Small short follow-up trial; altered composition without functional change does not establish systemic causality.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[61] Fecal microbiota transplantation for the improvement of metabolism in obesity: The FMT-TRIM double-blind placebo-controlled pilot trial.

Shows: FMT-TRIM achieves persistent donor engraftment without significant clamp insulin-sensitivity or body-composition benefit.

Does not show: Small pilot with mild insulin resistance and no paired dietary intervention; does not exclude modest or substrate-dependent effects.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC3, SC4.

[62] Autism-related dietary preferences mediate autism-gut microbiome associations.

Shows: Australian autism study detects little direct diagnostic microbiome association while diet/stool traits account for observed relationships.

Does not show: Cross-sectional mediation does not prove all gut-brain contributions absent; linked correction retained.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. Erratum in: PMID38242089. Subclaims: SC1, SC4.

[63] Stool consistency is strongly associated with gut microbiota richness and composition, enterotypes and bacterial growth rates.

Shows: Stool consistency correlates with richness, enterotypes and taxa including Akkermansia.

Does not show: Bristol score is a proxy; direct temporal transit-to-community causation is not isolated.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC4.

[64] Gut microbiota from multiple sclerosis patients enables spontaneous autoimmune encephalomyelitis in mice.

Shows: MS-discordant twin transfer increases spontaneous autoimmunity in transgenic recipients; IL-10 interruption changes protected recipients.

Does not show: Host autoreactive genotype is essential context; transfer is not endogenous human MS initiation.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC2, SC4.

[65] Commensal microbiota and myelin autoantigen cooperate to trigger autoimmune demyelination.

Shows: Commensal flora and host myelin autoantigen cooperate in spontaneous autoimmune demyelination in a defined mouse model.

Does not show: Host autoreactive repertoire and antigen context constrain generalization; microbiota is not an autonomous human initiator.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

[66] Gut flora metabolism of phosphatidylcholine promotes cardiovascular disease.

Shows: Dietary choline/TMAO and microbial suppression alter mouse foam-cell accumulation and atherosclerosis, with human metabolite-risk association.

Does not show: Hyperlipidemic mouse genotype and dietary exposure define scope; observational clinical metabolite risk is distinct from causal prevention.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC1, SC2, SC4.

[67] Gut-residing segmented filamentous bacteria drive autoimmune arthritis via T helper 17 cells.

Shows: Single SFB colonization reinstates Th17/autoantibody responses and arthritis in germ-free K/BxN mice; IL-17 neutralization prevents disease.

Does not show: Autoreactive host genotype is prerequisite; single strain is causal within this mouse context, not across human autoimmunity.

Access/status: Complete primary abstract and linked-status metadata examined. No complete-paper or supplement audit claimed. none_found. Subclaims: SC2, SC4.

Documentary record

Every grade on this site is reproducible from its record. The files below are the posted edition exactly as assessed.

• ADVERSARIAL_REVIEW.md
• SHA256.txt
• adversarial-findings.json
• codex-correction-provenance.json
• consensus-addendum.md
• consensus-validation.json
• edition-approval-audit.json
• microbiome-causality.review.md
• microbiome-causality.scorecard.json
• reader-summary.json
• validation-report.json
• validation-round2-2026-10-14.json
• validation.txt

Sources: 67 · load-bearing claims: 72 · verified: 72 · unverified: 0 · contradicted: 0 · schema 5.3