Evidence record

How much of you is you?

Every sentence on the exploration belongs to at least one claim below. Each says what kind of statement it is, what it rests on, what the evidence does not establish, and how far it was checked. Nothing here is a score, and none of it is a verdict on a belief or a theory.

Last checked 24 September 2026.

Source checked: 32
A judgement, not a fact: 12
Partly checked: 9

If something here is wrong, misquoted, out of date or unfair, write to support@unknownoceans.com and give the claim number, which does not change.

What the question takes for granted

A scientific question with two halves. The first, how many of a body’s cells are bacterial, is a matter of counting and has a well-sourced answer. The second, how much those bacteria shape health, is where the page’s uncertainty lives.

Counting cells measures how much of a body is its own
Contested
The answer depends on what is counted. Red blood cells, which have no nucleus, make up most human cells; leave them out and the ratio returns to about ten to one. By mass, the bacteria are a small fraction of a body.
The cells of a body can be counted with useful precision
Established
Established as an estimate with stated uncertainty, from measured concentrations and volumes, and two independent estimates agree to within a few trillion human cells.
Differences in the gut community cause differences in health
Open
Shown for recurrent C. difficile infection and in animal experiments. For most human conditions the evidence is association, and whether the community is cause, consequence or bystander is unresolved.

How the question is labelled

Claim: The passengers

Kind: Framing. Signposting. It asserts nothing a source could check.

The page’s title, a figure for the bacteria a body carries.

Claim: Microbiome

Kind: Framing. Signposting. It asserts nothing a source could check.

The question

Claim: The ratio of bacterial cells to human cells was quoted as ten to one for forty years.

Kind: Historical claim. A statement about the past that historical evidence can test.
Review: Source checked. The cited passage was read, and it says this.

Forty years is the span from the 1972 estimate the figure traces to, to the 2016 recount.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the BodyIntroduction; reference 3 (Luckey, Am J Clin Nutr, 1972)
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Texts · Review of the field
The source reads: we also revisit the 10:1 value that has been so thoroughly repeated as to achieve the status of an established common knowledge fact

Claim 3 · checked 24 September 2026 · AI-assisted audit

Claim: Someone finally checked.

Kind: Historical claim. A statement about the past that historical evidence can test.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the BodyIntroduction
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Texts · Review of the field
The source reads: This ratio was criticized recently in a letter to the journal Microbe [5], but an alternative detailed estimate that will give concrete values and estimate the uncertainty range is needed.

What this does not establish

The figure had been questioned before, in a 2014 letter; the 2016 paper was the first detailed recount.

Claim 4 · checked 24 September 2026 · AI-assisted audit

Claim: A human body carries roughly as many bacterial cells as human ones

Kind: Present-day figure. A count, survey or report finding, as the named source gives it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the Bodyabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: showing that the number of bacteria in the body is actually of the same order as the number of human cells
Supports
The human cell count and size distributionIntroduction
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: with total counts converging on values of 30 to 37 trillion human cells (16, 17), with an approximately equal number of bacteria cells (17)

What this does not establish

An estimate for a reference adult built from measured concentrations and volumes, not a count of any one body.

Later work looked for

Crossref, 2017 on, "number of bacteria human cells body": Hatton and colleagues (2023) recount human cells at about 36 trillion; the ratio stays near one to one. Page updated in claim 17.

Claim 5 · checked 24 September 2026 · AI-assisted audit

Claim: a figure that corrected a much-repeated estimate.

Kind: Historical claim. A statement about the past that historical evidence can test.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the BodyThe Ratio of Bacteria to Human Cells in the Adult Body
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: This B/H value of about 1:1 (with the associated uncertainty range) should replace the 10:1 or 100:1 values that are stated in the literature

Claim 6 · checked 24 September 2026 · AI-assisted audit

Claim: What those bacteria do to health, mood and development is a field with many correlations, a few demonstrated mechanisms, and a large gap between the two.

Kind: This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review: A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

The page’s summary of its second half, claims 49 to 65. The correlations are many rather than strong: the obesity association the page examines is, in the pooled analysis it cites, weak.

Context
Looking for a signal in the noise: revisiting obesity and the microbiomeabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Meta-analysis
The source reads: this association was relatively weak and its detection is confounded by large interpersonal variation and insufficient sample sizes
Context
Establishing or exaggerating causality for the gut microbiome: lessons from human microbiota-associated rodentsabstract
Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in animals · Review of the field
The source reads: whether such changes are causal, consequential, or bystanders to disease is, for the most part, unresolved

Corrected

24 September 2026. Previously: “a field with strong correlations” The pooled reanalysis the page cites calls the obesity association relatively weak; “strong” overstated it.

Claim 7 · checked 24 September 2026 · AI-assisted audit

Claim: The ten to one figure came from a back-of-the-envelope calculation in the 1970s

Kind: Historical claim. A statement about the past that historical evidence can test.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the BodyIntroduction; Revisiting the Original Back-of-the-Envelope Estimate
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Texts · Review of the field
The source reads: all papers regarding the number of bacteria in the human gastrointestinal tract that gave reference to the value stated could be traced to a single back-of-the-envelope estimate ... The primary source for the often cited value ... dates back to the 1970s

What this does not establish

The 1972 calculation estimated the number of bacteria; the ratio comes from setting that number beside an estimate of human cells.

Claim 8 · checked 24 September 2026 · AI-assisted audit

Claim: repeated until it became a fact everybody knew.

Kind: Historical claim. A statement about the past that historical evidence can test.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the BodyIntroduction
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Texts · Review of the field
The source reads: so thoroughly repeated as to achieve the status of an established common knowledge fact

Claim 9 · checked 24 September 2026 · AI-assisted audit

Claim: The recalculation is a good demonstration of how a number survives without ever being checked, and of what checking looks like.

Kind: This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review: A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

The page’s own judgement. It follows from claims 8 and 9: the figure traced to one sentence-long estimate, and the recount laid out its sources and uncertainty.

Claim 10 · checked 24 September 2026 · AI-assisted audit

What is there

Claim: What is there

Kind: Framing. Signposting. It asserts nothing a source could check.

About one to one

Claim: About one to one

Kind: Present-day figure. A count, survey or report finding, as the named source gives it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the BodyThe Ratio of Bacteria to Human Cells in the Adult Body
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: This B/H value of about 1:1

Later work looked for

Crossref, 2017 on, "human cell count": Hatton and colleagues (2023) leave the two numbers about equal.

Claim 12 · checked 24 September 2026 · AI-assisted audit

Claim: A 2016 analysis worked from measured concentrations and volumes

Kind: What scholars argue. A report of what specialists argue, or where they disagree.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the BodyDistribution of Bacteria in Different Human Organs
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: The estimates are based on multiplying measured concentrations of bacteria by the volume of each organ

Claim 13 · checked 24 September 2026 · AI-assisted audit

Claim: most of the bacteria are in the colon, which holds about 0.4 litres, not the litre of gut the older estimate multiplied by.

Kind: Present-day figure. A count, survey or report finding, as the named source gives it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the BodyRevisiting the Original Back-of-the-Envelope Estimate; Box 1
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: which assumes the volume of the alimentary tract to be 1 liter ... the parts of the alimentary tract proximal to the colon contain a negligible number of bacteria in comparison to the colon content ... we integrated data sources on the volume of the colon to arrive at 0.4 L

What this does not establish

The 0.4 litres is colon content for a 70 kg reference man, averaged from MRI and other studies, with a coefficient of variation of 25 per cent.

Later work looked for

Crossref, 2017 on, "colon volume bacteria number estimate": nothing that revises the colon volume.

Corrected

24 September 2026. Previously: “most of the bacteria are in the colon, and the colon is smaller than the older estimate assumed.” The older estimate did not assume a size for the colon: it applied colon density to a litre of the whole alimentary tract. Stated as the paper gives it.

Claim 14 · checked 24 September 2026 · AI-assisted audit

Claim: Human cells are dominated by red blood cells, which are numerous and small.

Kind: Present-day figure. A count, survey or report finding, as the named source gives it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the BodyComparing cell number and mass
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: The cell count is dominated by red blood cells (84%), among the smallest cell types in the human body with a volume of about 100 μm3.
Supports
The human cell count and size distributionResults
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: Cell counts are completely dominated by red blood cells, platelets, and tissue resident white blood cells

Later work looked for

Crossref, 2017 on, "human cell count": Hatton and colleagues (2023) agree.

Claim 15 · checked 24 September 2026 · AI-assisted audit

Claim: The result for a reference adult is roughly 38 trillion bacteria to 30 trillion human cells.

Kind: Present-day figure. A count, survey or report finding, as the named source gives it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the Bodyabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: Thoroughly revised estimates show that the typical adult human body consists of about 30 trillion human cells and about 38 trillion bacteria.

What this does not establish

The reference adult is a 70 kg man aged 20 to 30. The paper puts the ratio for women, infants and the elderly between 1.3 and 2.3.

Later work looked for

Crossref, 2017 on, "number of bacteria human cells body": the human count was revised to about 36 trillion in 2023 (claim 17); no revision of the bacterial count found.

Claim 16 · checked 24 September 2026 · AI-assisted audit

Claim: A 2023 recount of human cells came to about 36 trillion, which leaves the two numbers about equal.

Kind: Present-day figure. A count, survey or report finding, as the named source gives it.
Review: Source checked. The cited passage was read, and it says this.

Supports
The human cell count and size distributionabstract; Introduction
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: we estimate total body counts of ≈36 trillion cells in the male ... with total counts converging on values of 30 to 37 trillion human cells (16, 17), with an approximately equal number of bacteria cells (17)

What this does not establish

For a 70 kg male; the same paper gives about 28 trillion for a 60 kg female. It counts human cells only and takes the bacterial number from the 2016 paper.

Later work looked for

This is the newer work; Crossref, 2024 on, "human cell count": nothing later found.

Corrected

24 September 2026. Previously: “” Currency: a later, larger compilation revised the human cell count. The ratio is unchanged in substance.

Claim 17 · checked 24 September 2026 · AI-assisted audit

Claim: The ratio varies between individuals and changes after a bowel movement

Kind: Present-day figure. A count, survey or report finding, as the named source gives it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the BodyThe Ratio of Bacteria to Human Cells in the Adult Body; Box 1
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: a variation of 53% over the population of standard 70 kg males ... each defecation event reduces the content by a quarter to a third

What this does not establish

The paper reports the fall in colon content; the change in the ratio is inferred from it.

Later work looked for

Crossref, 2017 on, as for claim 16: nothing that changes it.

Claim 18 · checked 24 September 2026 · AI-assisted audit

Claim: which says something about the precision available.

Kind: This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review: A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

Follows from claim 18 and from the paper’s own account of its uncertainty.

Context
Revised Estimates for the Number of Human and Bacteria Cells in the BodyDiscussion
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: These knowledge gaps indicate that there might be systematic errors beyond what we could account for in the uncertainty ranges we report.

Claim 19 · checked 24 September 2026 · AI-assisted audit

Claim: By mass the bacteria are a fraction of a kilogram.

Kind: Present-day figure. A count, survey or report finding, as the named source gives it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the Bodyabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: their total mass is about 0.2 kg

Later work looked for

Crossref, 2017 on, as for claim 16: nothing that changes it.

Claim 20 · checked 24 September 2026 · AI-assisted audit

Claim: The imagery of being outnumbered and overwhelmed was doing a lot of work that the numbers do not support.

Kind: This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review: A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

The page’s judgement on the imagery, not on the bacteria: the paper’s authors add that the smaller ratio leaves their biological importance where it was, which the next passage takes up.

Context
Revised Estimates for the Number of Human and Bacteria Cells in the BodyDiscussion
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: Updating the ratio of bacteria to human cells from 10:1 or 100:1 to closer to 1:1 does not take away from the biological importance of the microbiota.

Claim 21 · checked 24 September 2026 · AI-assisted audit

Claim: What the recount changed

Kind: Framing. Signposting. It asserts nothing a source could check.

Claim: You are ten per cent human.

Kind: Framing. Signposting. It asserts nothing a source could check.

The misconception the entry corrects. The page does not assert it.

Claim: Roughly half your cells are bacterial, and by mass they are a small fraction of you.

Kind: Present-day figure. A count, survey or report finding, as the named source gives it.
Review: Source checked. The cited passage was read, and it says this.

At 38 trillion bacteria to 30 trillion human cells, bacteria are about 56 per cent of the total.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the Bodyabstract; section on bacterial mass
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: we identify the dominant role of the hematopoietic lineage to the total count (≈90%) and revise past estimates to 3.0·1013 human cells ... The total bacteria mass we find represents about 0.3% of the overall body weight

Later work looked for

Crossref, 2017 on, as for claim 16: the 2023 human count leaves it about half.

Claim 24 · checked 24 September 2026 · AI-assisted audit

Claim: The old figure was a measurement.

Kind: Framing. Signposting. It asserts nothing a source could check.

The misconception the entry corrects. The page does not assert it.

Claim: It was an estimate made in passing in the 1970s, cited for forty years without being recalculated.

Kind: Historical claim. A statement about the past that historical evidence can test.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the BodyRevisiting the Original Back-of-the-Envelope Estimate
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Texts · Review of the field
The source reads: dates back to the 1970s [3] and only consists of a sentence-long “derivation,”

What this does not establish

The paper traces every citation of the bacterial count it examined to the one estimate; it does not claim to have searched every citation of the ratio.

Claim 26 · checked 24 September 2026 · AI-assisted audit

Claim: The ratio is a constant.

Kind: Framing. Signposting. It asserts nothing a source could check.

The misconception the entry corrects. The page does not assert it.

Claim: It varies between people and within a person across a day.

Kind: Present-day figure. A count, survey or report finding, as the named source gives it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Revised Estimates for the Number of Human and Bacteria Cells in the BodyThe Ratio of Bacteria to Human Cells in the Adult Body; Box 1
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Model
The source reads: a variation of 53% over the population of standard 70 kg males ... Following a typical meal, the volume changes by about 10% [15], while each defecation event reduces the content by a quarter to a third

Later work looked for

Crossref, 2017 on, as for claim 16: nothing that changes it.

Claim 28 · checked 24 September 2026 · AI-assisted audit

They are doing real work

Claim: They are doing real work

Kind: This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review: A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

A heading summarising claims 30 to 34.

Claim 29 · checked 24 September 2026 · AI-assisted audit

Claim: Gut bacteria break down complex carbohydrates the human gut cannot

Kind: What the field holds. The settled view of a field, as a review, a consensus statement or a reference work gives it. Not one study.
Review: Source checked. The cited passage was read, and it says this.

Supports
Microbial degradation of complex carbohydrates in the gutabstract; Introduction
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in microbes · Review of the field
The source reads: Mammalian genomes do not encode most of the enzymes needed to degrade the structural polysaccharides present in plant material.

Later work looked for

Crossref, 2012 on, "gut microbiota dietary fibre degradation review": later reviews extend the enzyme catalogue; nothing that changes it.

Claim 30 · checked 24 September 2026 · AI-assisted audit

Claim: some of them synthesise B vitamins

Kind: What the field holds. The settled view of a field, as a review, a consensus statement or a reference work gives it. Not one study.
Review: Source checked. The cited passage was read, and it says this.

Supports
Bacteria as vitamin suppliers to their host: a gut microbiota perspectiveIntroduction, first paragraph
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in microbes · Review of the field
The source reads: In humans it has been shown that members of the gut microbiota are able to synthesize vitamin K as well as most of the water-soluble B vitamins

What this does not establish

Synthesis is shown; how much of a person’s need the gut bacteria meet is less settled. The review says gut bacteria may only partially fulfil the requirement for B12.

Later work looked for

Crossref, 2013 on, "gut microbiota B vitamin synthesis": nothing that changes it.

Claim 31 · checked 24 September 2026 · AI-assisted audit

Claim: and colonisation shapes the adaptive immune system while it is developing.

Kind: What the field holds. The settled view of a field, as a review, a consensus statement or a reference work gives it. Not one study.
Review: Source checked. The cited passage was read, and it says this.

Supports
The gut microbiota shapes intestinal immune responses during health and diseaseabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field
The source reads: Here we discuss findings which indicate that developmental aspects of the adaptive immune system are influenced by intestinal bacterial colonization.

What this does not establish

Much of the evidence the review draws on is from germ-free and colonised animals.

Later work looked for

Crossref, 2009 on, "microbiota immune system development review": later reviews extend it; nothing that reverses it.

Claim 32 · checked 24 September 2026 · AI-assisted audit

Claim: Mice raised germ-free develop abnormal immune systems

Kind: Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review: Source checked. The cited passage was read, and it says this.

Supports
The gut microbiota shapes intestinal immune responses during health and diseasesection on the development of the immune system
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field
The source reads: Germ-free animals show extensive deficits in the development of the gut-associated lymphoid tissues (GALT)

What this does not establish

In mice and other laboratory animals, mostly in the tissues of the gut.

Later work looked for

Crossref, 2009 on, as for claim 32: nothing that changes it.

Claim 33 · checked 24 September 2026 · AI-assisted audit

Claim: and they move more and behave less anxiously than mice carrying a normal gut community.

Kind: Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review: Partly checked. Only part of the source could be read. What was not read is listed.

Supports
Normal gut microbiota modulates brain development and behaviorabstract
Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in animals · Experiment
The source reads: germ free (GF) mice display increased motor activity and reduced anxiety, compared with specific pathogen free (SPF) mice with a normal gut microbiota

What this does not establish

Read as an abstract only. “Less anxiously” means less anxiety-like behaviour on laboratory tests in mice, which is not anxiety in people.

Later work looked for

Crossref, 2011 on, "germ-free mice anxiety-like behavior microbiota": later germ-free studies report behavioural differences in the same direction; none read, page unchanged.

Claim 34 · checked 24 September 2026 · AI-assisted audit

Claim: That much is demonstrated by intervention rather than inferred from correlation.

Kind: This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review: A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

Follows from claims 30 to 34: each rests on experiment, in culture, in genomes or in germ-free animals, rather than on comparing groups of people.

What this does not establish

The immune and behavioural results are in mice. What the vitamins contribute to a person is less settled than that the bacteria make them.

Claim 35 · checked 24 September 2026 · AI-assisted audit

What a healthy one looks like

Claim: What a healthy one looks like

Kind: Framing. Signposting. It asserts nothing a source could check.

Claim: Before differences can mean anything, the normal range has to be known.

Kind: This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review: A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

The survey’s own statement of its purpose, put as a principle.

Context
Structure, function and diversity of the healthy human microbiomeabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Observational study: associations, not causes
The source reads: These results thus delineate the range of structural and functional configurations normal in the microbial communities of a healthy population

Claim 37 · checked 24 September 2026 · AI-assisted audit

Claim: A survey published in 2012 sampled 242 screened adults at up to eighteen body sites and sequenced what was there.

Kind: Observation. Something measured or seen, as the named source reports it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Structure, function and diversity of the healthy human microbiomemain text, first section
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Observational study: associations, not causes
The source reads: A total of 4,788 specimens from 242 screened and phenotyped adults ... Women were sampled at 18 body habitats, men at 15

What this does not establish

Healthy adults in a Western population, in the United States.

Later work looked for

Crossref, 2016 on, "expanded human microbiome project": the 2017 expansion of the same cohort; describes the survey, which later work does not revise.

Claim 38 · checked 24 September 2026 · AI-assisted audit

Claim: Its main finding was that the species present vary enormously between healthy people, while the metabolic functions those species perform are much more consistent.

Kind: Observation. Something measured or seen, as the named source reports it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Structure, function and diversity of the healthy human microbiomeabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Observational study: associations, not causes
The source reads: We found the diversity and abundance of each habitat’s signature microbes to vary widely even among healthy subjects ... Metagenomic carriage of metabolic pathways was stable among individuals despite variation in community structure

What this does not establish

What was measured is the genes for metabolic pathways in the community, not the chemistry those genes carry out.

Later work looked for

Crossref, 2016 on, "expanded human microbiome project strains functions": the 2017 expansion, 1,215 citations, was found and not read; page unchanged.

Claim 39 · checked 24 September 2026 · AI-assisted audit

Claim: That is part of why comparisons of species lists between sick and healthy groups have been hard to reproduce.

Kind: What scholars argue. A report of what specialists argue, or where they disagree.
Review: Source checked. The cited passage was read, and it says this.

Supports
Looking for a signal in the noise: revisiting obesity and the microbiomeabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Meta-analysis
The source reads: this association was relatively weak and its detection is confounded by large interpersonal variation and insufficient sample sizes

What this does not establish

Sze and Schloss say this of obesity; the page extends it to comparisons in general.

Claim 40 · checked 24 September 2026 · AI-assisted audit

Claim: Pooling ten obesity studies in 2016 found no consistent difference in the ratio of phyla everyone was quoting

Kind: Observation. Something measured or seen, as the named source reports it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Looking for a signal in the noise: revisiting obesity and the microbiomeabstract; Results
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Meta-analysis
The source reads: The preferred reporting items for systematic reviews and meta-analyses guidelines were used to identify 10 studies for an updated and more synthetic analysis. ... They were not observed for the ratio of Bacteroidetes and Firmicutes or their individual relative abundances.

What this does not establish

The same pooling did find small differences in diversity, 2.07 per cent in Shannon diversity.

Later work looked for

Crossref, 2016 on, "meta-analysis gut microbiome obesity": Chanda and De (2024) pool 3,329 samples and report predictive species; page updated in claim 43.

Corrected

24 September 2026. Previously: “Pooling ten obesity studies found” Dated, because later and larger pooled work (claim 43) reads differently.

Claim 41 · checked 24 September 2026 · AI-assisted audit

Claim: and a classifier trained on one of those datasets was right about 57 per cent of the time on the rest.

Kind: Observation. Something measured or seen, as the named source reports it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Looking for a signal in the noise: revisiting obesity and the microbiomeabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Meta-analysis
The source reads: When random forest machine learning models were trained on one data set and then tested by using the other nine data sets, the median accuracy varied between 33.01 and 64.77% (median, 56.68%).

What this does not establish

57 per cent is the median across the ten models; the range ran from 33 to 65.

Later work looked for

As for claim 41.

Corrected

24 September 2026. Previously: “did little better than chance on the rest.” The paper gives the accuracy and calls the classification relatively poor; it does not compare it with chance. The page now gives the figure.

Claim 42 · checked 24 September 2026 · AI-assisted audit

Claim: A 2024 analysis of 3,329 samples from seventeen countries reports a set of species that predicted obesity well in an independent dataset

Kind: Observation. Something measured or seen, as the named source reports it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Meta-analysis reveals obesity associated gut microbial alteration patterns and reproducible contributors of functional shiftabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Meta-analysis
The source reads: using 3329 samples (Obese, n = 1494; Control, n = 1835) from 17 different countries ... We identified 25 highly predictive species and 37 pathway associations as signatures of obesity, which were validated with remarkably high accuracy (AUC, Species: 0.85, and pathway: 0.80) with an independent validation dataset.

What this does not establish

One analysis, not yet a consensus. It uses metagenomic data where the 2016 pooling used 16S sequencing, and prediction is association, not cause.

Later work looked for

This is the newer work; nothing later found in the same Crossref search.

Corrected

24 September 2026. Previously: “” Currency: a larger pooled analysis reads the obesity signal differently from the 2016 one. Reported beside it.

Claim 43 · checked 24 September 2026 · AI-assisted audit

Claim: so the signal may be real and small rather than absent.

Kind: This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review: A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

Follows from claims 41 to 43, and is the 2016 authors’ own reading: an association, weak and hard to detect across small studies.

Context
Looking for a signal in the noise: revisiting obesity and the microbiomeabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Meta-analysis
The source reads: Although there was support for a relationship between the microbial communities found in human feces and obesity status, this association was relatively weak

Claim 44 · checked 24 September 2026 · AI-assisted audit

Claim: The stable quantity is what the community does, not who is in it.

Kind: This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review: A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

The page’s reading of claim 39.

What this does not establish

Stable means carried by most healthy people’s communities, as genes, not measured activity.

Claim 45 · checked 24 September 2026 · AI-assisted audit

What it does

Claim: What it does

Kind: Framing. Signposting. It asserts nothing a source could check.

Claim: A number can live for forty years on being repeated.

Kind: This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review: A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

The page’s reading of claims 3, 8 and 9.

Claim 47 · checked 24 September 2026 · AI-assisted audit

How much of health this explains

Claim: How much of health this explains

Kind: Framing. Signposting. It asserts nothing a source could check.

Claim: Differences in gut communities are associated with obesity, inflammatory disease, allergy, and depression.

Kind: Observation. Something measured or seen, as the named source reports it.
Review: Source checked. The cited passage was read, and it says this.

Supports
Looking for a signal in the noise: revisiting obesity and the microbiomeabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Meta-analysis
The source reads: Although there was support for a relationship between the microbial communities found in human feces and obesity status
Supports
The gut microbiota shapes intestinal immune responses during health and diseasesections on IBD and on allergy
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field
The source reads: The results revealed a statistically significant difference between the microbial compositions of IBD patients and non-IBD patient controls. ... Epidemiological studies have linked an altered intestinal microbiota to other allergic disorders, such as atopic eczema
Supports
Gut microbiome-wide association study of depressive symptomsabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Observational study: associations, not causes
The source reads: We identify association of thirteen microbial taxa ... with depressive symptoms

What this does not establish

Associations, from observational studies. The depression result is from two Dutch cohorts, 1,054 and 1,539 people, and concerns symptoms rather than diagnosis.

Later work looked for

Europe PMC, 2016 on, obesity, IBD and depression microbiome studies: the associations continue to be reported; the obesity signal is read differently by Chanda and De (claim 43).

Claim 49 · checked 24 September 2026 · AI-assisted audit

Claim: Association is where most of these results stop.

Kind: What scholars argue. A report of what specialists argue, or where they disagree.
Review: Partly checked. Only part of the source could be read. What was not read is listed.

Supports
Establishing or exaggerating causality for the gut microbiome: lessons from human microbiota-associated rodentsabstract
Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in animals · Review of the field
The source reads: whether such changes are causal, consequential, or bystanders to disease is, for the most part, unresolved
Context
The gut microbiota shapes intestinal immune responses during health and diseasesection on IBD
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field
The source reads: It remains unclear whether dysbiosis directly causes disease or is a result of the altered intestinal environment.

What this does not establish

Walter and colleagues were read as an abstract only.

Claim 50 · checked 24 September 2026 · AI-assisted audit

Claim: Transplant experiments in mice sometimes transfer a trait along with a community

Kind: Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review: Source checked. The cited passage was read, and it says this.

Supports
The gut microbiota shapes intestinal immune responses during health and diseasesection on dysbiosis
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field
The source reads: transfer of the microbiota from ob/ob animals into germ-free wild-type animals results in an increase in the mean body fat of recipient animals
Supports
Gut microbiota from twins discordant for obesity modulate metabolism in miceabstract
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Experiment
The source reads: Increased total body and fat mass, as well as obesity-associated metabolic phenotypes were transmissible with uncultured fecal communities

Later work looked for

Crossref, 2020 on, "human microbiota-associated rodents causality": transfer studies continue; nothing that changes the claim.

Claim 51 · checked 24 September 2026 · AI-assisted audit

Claim: which is stronger evidence, and mice are not people.

Kind: This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review: A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

An intervention tests a cause where an association cannot; the step from mouse to person is the one Walter and colleagues question.

Context
Establishing or exaggerating causality for the gut microbiome: lessons from human microbiota-associated rodentsabstract
Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in animals · Review of the field
The source reads: many extrapolated the findings to make causal inferences to human diseases

Claim 52 · checked 24 September 2026 · AI-assisted audit

Claim: Germ-free mice given the gut community of an obese twin gained more fat than mice given her lean co-twin’s.

Kind: Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review: Source checked. The cited passage was read, and it says this.

Supports
Gut microbiota from twins discordant for obesity modulate metabolism in miceResults, first section
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Experiment
The source reads: the change in adipose mass of mice that received an obese co-twin’s fecal microbiota was significantly greater than the change in animals receiving her lean twin’s gut community

What this does not establish

Four twin pairs, all women, and 103 mice. The effect depended on diet, and housing obese-twin mice with lean-twin mice prevented it.

Later work looked for

Crossref, 2020 on, as for claim 51; Walter and colleagues (claim 54) question what such transfers show for people.

Corrected

24 September 2026. Previously: “Transplanting the gut community of an obese twin into germ-free mice raised their body and fat mass, where the lean co-twin’s community did not.” The paper compares the change in fat between the two groups of mice; it does not say the lean twin’s community caused no gain.

Claim 53 · checked 24 September 2026 · AI-assisted audit

Claim: One systematic review found that 36 of 38 published transfer studies reported the phenotype crossing into the animals

Kind: Present-day figure. A count, survey or report finding, as the named source gives it.
Review: Partly checked. Only part of the source could be read. What was not read is listed.

Supports
Establishing or exaggerating causality for the gut microbiome: lessons from human microbiota-associated rodentsabstract
Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in animals · Review of the field
The source reads: In a systematic review, we found that 95% of published studies (36/38) on HMA rodents reported a transfer of pathological phenotypes to recipient animals

What this does not establish

Read as an abstract only; the table of the 38 studies was not read.

Later work looked for

Crossref, 2020 on, "human microbiota-associated rodents causality": no later count or reply found.

Claim 54 · checked 24 September 2026 · AI-assisted audit

Claim: and argued that a success rate that high is not plausible and overstates what the microbiome does in human disease.

Kind: What scholars argue. A report of what specialists argue, or where they disagree.
Review: Partly checked. Only part of the source could be read. What was not read is listed.

Supports
Establishing or exaggerating causality for the gut microbiome: lessons from human microbiota-associated rodentsabstract
Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in animals · Review of the field
The source reads: We posit that this exceedingly high rate of inter-species transferable pathologies is implausible and overstates the role of the gut microbiome in human disease.

What this does not establish

Read as an abstract only. This is the authors’ argument, not a measured result.

Claim 55 · checked 24 September 2026 · AI-assisted audit

Whether anything can be done deliberately

Claim: Whether anything can be done deliberately

Kind: Framing. Signposting. It asserts nothing a source could check.

Claim: Faecal transplantation is an established treatment for one condition, recurrent Clostridium difficile infection

Kind: What the field holds. The settled view of a field, as a review, a consensus statement or a reference work gives it. Not one study.
Review: Source checked. The cited passage was read, and it says this.

Supports
European consensus conference on faecal microbiota transplantation in clinical practiceIntroduction; section on other indications
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Consensus statement
The source reads: proved clear evidence that FMT is a highly effective treatment against recurrent Clostridium difficile infection (rCDI) ... for none of them emerged an evidence-based recommendation to use FMT except that in a context of research

What this does not establish

A European consensus of 2017. Ulcerative colitis has since gathered trials (claim 60), without a recommendation of the same strength.

Later work looked for

Europe PMC, 2020 on, faecal transplantation systematic reviews: the 2023 Cochrane review for recurrent C. difficile (abstract read) finds a large increase in resolution on moderate-certainty evidence; the 2023 Cochrane review for IBD qualifies “one condition”, and the page now reports it.

Corrected

24 September 2026. Previously: “Faecal transplantation is genuinely effective for one condition” Carried by a consensus statement rather than by one trial, and narrowed to what it says: established for this condition, not shown ineffective for all others.

Claim 57 · checked 24 September 2026 · AI-assisted audit

Claim: and that is the clearest clinical result the field has.

Kind: This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review: A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

Follows from claim 57: the only use of a microbial therapy the consensus recommends outside research.

Claim 58 · checked 24 September 2026 · AI-assisted audit

Claim: One of the trials behind it was stopped early: 13 of 16 patients given donor faeces recovered after the first infusion, against 4 of 13 on vancomycin alone.

Kind: Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review: Partly checked. Only part of the source could be read. What was not read is listed.

Supports
Duodenal infusion of donor feces for recurrent Clostridium difficileabstract, Results
Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Trial
The source reads: The study was stopped after an interim analysis. Of 16 patients in the infusion group, 13 (81%) had resolution of C. difficile-associated diarrhea after the first infusion. ... Resolution of C. difficile infection occurred in 4 of 13 patients (31%) receiving vancomycin alone

What this does not establish

Read as an abstract only. The infusion followed a short course of vancomycin and bowel lavage. A small trial: 43 patients in three arms.

Later work looked for

Europe PMC, 2020 on: the 2023 Cochrane review pools six trials, 320 people, and agrees in direction.

Corrected

24 September 2026. Previously: “The trial that showed it was stopped early: 13 of 16 patients were cured by a single infusion of donor faeces, against 4 of 13 on vancomycin alone.” The consensus rests on several trials, not one. The trial measured resolution of diarrhoea without relapse at ten weeks, which “cured” overstated, and the infusion group had vancomycin and lavage first.

Claim 59 · checked 24 September 2026 · AI-assisted audit

Claim: For ulcerative colitis, trials suggest it may help, on evidence of low certainty.

Kind: Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review: Partly checked. Only part of the source could be read. What was not read is listed.

Supports
Fecal transplantation for treatment of inflammatory bowel diseaseabstract, Main results
Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Meta-analysis
The source reads: FMT may increase rates of induction of clinical remission in UC compared to control (risk ratio (RR) 1.79, 95% confidence interval (CI) 1.13 to 2.84; low-certainty evidence)

What this does not establish

Read as an abstract only. Ten trials, 468 people, for inducing remission; the evidence on keeping it, and on Crohn’s disease, is very uncertain.

Later work looked for

This is the newer work; the Cochrane review’s search runs to 2022.

Corrected

24 September 2026. Previously: “” Currency: trials since the page’s sources give a low-certainty benefit in one more condition.

Claim 60 · checked 24 September 2026 · AI-assisted audit

Claim: Commercial probiotics are a different matter.

Kind: Framing. Signposting. It asserts nothing a source could check.

Claim: Whether a strain settles in the gut at all varies from person to person

Kind: Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review: Partly checked. Only part of the source could be read. What was not read is listed.

Supports
Personalized gut mucosal colonization resistance to empiric probiotics is associated with unique host and microbiome featuresabstract
Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Trial
The source reads: humans featured person-, region- and strain-specific mucosal colonization patterns, hallmarked by predictive baseline host and microbiome features, but indistinguishable by probiotics presence in stool

What this does not establish

Read as an abstract only. One study, with an 11-strain combination, sampling the gut lining directly in a small number of people.

Later work looked for

Crossref, 2018 on, "probiotic colonization resistance gut mucosa": nothing found that changes it.

Claim 62 · checked 24 September 2026 · AI-assisted audit

Claim: and in trials the effects depend on the strain and on the condition.

Kind: What the field holds. The settled view of a field, as a review, a consensus statement or a reference work gives it. Not one study.
Review: Source checked. The cited passage was read, and it says this.

Supports
Strain-specificity and disease-specificity of probiotic efficacy: a systematic review and meta-analysisabstract, Conclusion
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Meta-analysis
The source reads: Strong evidence was found supporting the hypothesis that the efficacy of probiotics is both strain-specific and disease-specific.

What this does not establish

228 trials in people with a condition to prevent or treat, not in healthy people.

Later work looked for

Crossref, 2018 on, "probiotic strain-specific efficacy": nothing found that changes it.

Corrected

24 September 2026. Previously: “effects are strain-specific and condition-specific” Had no source on the page; now cited to a meta-analysis of 228 trials.

Claim 63 · checked 24 September 2026 · AI-assisted audit

Claim: In healthy adults, one review of trials found benefits for a few measures, stool consistency among them

Kind: Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review: Partly checked. Only part of the source could be read. What was not read is listed.

Supports
A review of probiotic supplementation in healthy adults: helpful or hype?abstract
Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Review of the field
The source reads: Evidence also supports the role of probiotics in improving immune system responses, stool consistency, bowel movement, and vaginal lactobacilli concentration.

What this does not establish

Read as an abstract only. A narrative review of 45 trials, not a meta-analysis, and the authors say benefit in healthy adults needs further investigation.

Later work looked for

Crossref, 2019 on, "probiotic supplementation healthy adults review": nothing found that changes it.

Corrected

24 September 2026. Previously: “and the evidence for general benefit in healthy people is weak.” Unsourced, and a review of trials in healthy adults reports some benefits. Replaced with what two reviews found.

Claim 64 · checked 24 September 2026 · AI-assisted audit

Claim: and two found little sign of a lasting change to the gut community.

Kind: Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review: Partly checked. Only part of the source could be read. What was not read is listed.

Supports
Alterations in fecal microbiota composition by probiotic supplementation in healthy adults: a systematic review of randomized controlled trialsabstract, Conclusions
Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field
The source reads: demonstrates a lack of evidence for an impact of probiotics on fecal microbiota composition in healthy adults
Supports
A review of probiotic supplementation in healthy adults: helpful or hype?abstract
Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Review of the field
The source reads: this review failed to support the ability of probiotics to cause persistent changes in gut microbiota

What this does not establish

Khalesi and colleagues were read as an abstract only. Kristensen and colleagues reviewed seven trials and measured stool, not the gut lining.

Later work looked for

Crossref, 2016 on, "probiotic healthy adults fecal microbiota systematic review": nothing found that changes it.

Claim 65 · checked 24 September 2026 · AI-assisted audit

What was read

Revised Estimates for the Number of Human and Bacteria Cells in the BodySender, Fuchs and Milo, PLOS Biology · Europe PMC full text, PMC4991899Read in full, 24 September 2026 · CC BY 4.0The supplementary appendix and data tables were not read.
Microbial degradation of complex carbohydrates in the gutFlint and others, Gut Microbes · Europe PMC full text, PMC3463488Read in full, 24 September 2026 · CC BY-NC
Bacteria as vitamin suppliers to their host: a gut microbiota perspectiveLeBlanc and others, Current Opinion in Biotechnology · Accepted copy in the CONICET repository (ri.conicet.gov.ar, handle 11336/2561), read as PDFRead in full, 24 September 2026 · Copyright; quoted briefly
The gut microbiota shapes intestinal immune responses during health and diseaseRound and Mazmanian, Nature Reviews Immunology · Author manuscript, NCBI PMC4095778 via E-utilitiesRead in full, 24 September 2026 · Copyright; author manuscript; quoted brieflyThe manuscript is titled “The gut microbiome shapes intestinal immune responses during health and disease”; the published title says “microbiota”.
Normal gut microbiota modulates brain development and behaviorDiaz Heijtz and others, Proceedings of the National Academy of Sciences · Europe PMC record, PMID 21282636Abstract only, 24 September 2026 · Copyright; quoted brieflyPMC3041077 carries only the front matter in XML, and the publisher refuses this environment. The Results were not read.
Structure, function and diversity of the healthy human microbiomeHuman Microbiome Project Consortium, Nature · Author manuscript, NCBI PMC3564958 via E-utilitiesRead in full, 24 September 2026 · Copyright; author manuscript; quoted brieflyThe supplementary tables and figures were not read.
Looking for a signal in the noise: revisiting obesity and the microbiomeSze and Schloss, mBio · Europe PMC full text, PMC4999546Read in full, 24 September 2026 · CC BY 4.0
Gut microbiota from twins discordant for obesity modulate metabolism in miceRidaura and others, Science · Author manuscript, NCBI PMC3829625 via E-utilitiesRead in full, 24 September 2026 · Copyright; author manuscript; quoted brieflyThe manuscript is titled “Cultured gut microbiota from twins discordant for obesity modulate adiposity and metabolic phenotypes in mice”; it is the same paper.
Establishing or exaggerating causality for the gut microbiome: lessons from human microbiota-associated rodentsWalter and others, Cell · Europe PMC record, PMID 31978342Abstract only, 24 September 2026 · Copyright; quoted brieflyThe open copy unpaywall lists at cell.com refuses this environment. The body of the review, including its table of the 38 studies, was not read.
Duodenal infusion of donor feces for recurrent Clostridium difficilevan Nood and others, New England Journal of Medicine · Europe PMC record, PMID 23323867Abstract only, 24 September 2026 · Copyright; quoted brieflyThe publisher’s PDF and the Wageningen repository page both refused this environment.
Personalized gut mucosal colonization resistance to empiric probiotics is associated with unique host and microbiome featuresZmora and others, Cell · Europe PMC record, PMID 30193112Abstract only, 24 September 2026 · Copyright; quoted brieflyThe open copy unpaywall lists at cell.com refuses this environment.
The human cell count and size distributionHatton and others, Proceedings of the National Academy of Sciences · Europe PMC full text, PMC10523466Read in full, 24 September 2026 · CC BY-NC-ND 4.0The SI Appendix was not read.
Meta-analysis reveals obesity associated gut microbial alteration patterns and reproducible contributors of functional shiftChanda and De, Gut Microbes · Europe PMC full text, PMC10810176Read in full, 24 September 2026 · CC BY 4.0
Gut microbiome-wide association study of depressive symptomsRadjabzadeh and others, Nature Communications · Europe PMC full text, PMC9726982Read in full, 24 September 2026 · CC BY 4.0
European consensus conference on faecal microbiota transplantation in clinical practiceCammarota and others, Gut · Europe PMC full text, PMC5529972Read in full, 24 September 2026 · CC BY-NC 4.0Online supplementary 1, on indications other than C. difficile, was not read.
Fecal transplantation for treatment of inflammatory bowel diseaseImdad and others, Cochrane Database of Systematic Reviews · Europe PMC record, PMID 37094824Abstract only, 24 September 2026 · Copyright; quoted briefly
Strain-specificity and disease-specificity of probiotic efficacy: a systematic review and meta-analysisMcFarland and others, Frontiers in Medicine · Europe PMC full text, PMC5949321Read in full, 24 September 2026 · CC BY 4.0
A review of probiotic supplementation in healthy adults: helpful or hype?Khalesi and others, European Journal of Clinical Nutrition · Europe PMC record, PMID 29581563Abstract only, 24 September 2026 · Copyright; quoted brieflyA narrative review of 45 trials, 1990 to August 2017. The body was not read.
Alterations in fecal microbiota composition by probiotic supplementation in healthy adults: a systematic review of randomized controlled trialsKristensen and others, Genome Medicine · Europe PMC full text, PMC4862129Read in full, 24 September 2026 · CC BY 4.0