41/100
The human microbiota has a fundamental role in host physiology and pathology. 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
Research
28,180 Alzheimer's and dementia studies in plain English, each scored out of 100.
The self-renewing epithelium of the small intestine is ordered into stem/progenitor crypt compartments and differentiated villus compartments. 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
41/100
Alzheimer's disease is the most common form of dementia in the western world, however there is no cure available for this devastating neurodegenerative disorder. 3 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
One of the most important scientific discoveries of recent years was the disclosure that the intestinal microflora takes part in bidirectional communication between the gut and the brain. 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
The clinical manifestations of AIDS (acquired immune deficiency syndrome) often include neuropsychiatric and neurological deficits, including early memory loss and progressive dementia. 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
41/100
Understanding how gut flora influences gut-brain communications has been the subject of significant research over the past decade. 3 key findings →
Design: narrative review Evidence: low
Full summary, score breakdown and related studies → Original source
Almost half the cells and 1% of the unique genes found in our bodies are human, the rest are from microbes, predominantly bacteria, archaea, fungi, and viruses. 5 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
Gut microbiota has a proven role in regulating multiple neuro-chemical pathways through the highly interconnected gut-brain axis. 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
The endotoxin hypothesis of neurodegeneration is the hypothesis that endotoxin causes or contributes to neurodegeneration. 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
The intestinal barrier is essential in human health and constitutes the interface between the outside and the internal milieu of the body. 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
Alzheimer's disease (AD) is a neurodegenerative disease whose various pathophysiological aspects are still being investigated. 3 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
Although the potential contribution of the human gastrointestinal (GI) tract microbiome to human health, aging, and disease is becoming increasingly acknowledged, the molecular mechanics and signaling pathways of just how this is accomplished is not well-understood. 5 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
There is increasing evidence showing that the dynamic changes in the gut microbiota can alter brain physiology and behavior. 5 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
It has previously been shown that the consumption of probiotics may have beneficial effects not only on peripheral tissues but also on the central nervous system and behavior via the microbiota-gut-brain axis, raising the possibility that treatment with probiotics could be an effective therapeutic strategy for managing neurodegenerative disorders. 5 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
Metabolic syndrome, which includes diabetes and obesity, is one of the most widespread medical conditions. 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
Akk effectively improved glucose tolerance, intestine barrier dysfunction and dyslipidemia in AD model mice. 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
Inflammation is a protective reaction activated in response to detrimental stimuli, such as dead cells, irritants or pathogens, by the evolutionarily conserved immune system and is regulated by the host. 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
Recent evidence suggests the commensal microbiome regulates host immunity and influences brain function; findings that have ramifications for neurodegenerative diseases. 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
41/100
Neurovascular integrity, including cerebral blood flow (CBF) and blood-brain barrier (BBB) function, plays a major role in determining cognitive capability. 5 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
The gut microbiota has been linked to various neurological disorders via the gut-brain axis. 5 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
Dementia is a comprehensive category of brain diseases that is great enough to affect a person's daily functioning. 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
Neurological diseases, such as Parkinson's disease, Alzheimer's disease, amyotrophic lateral sclerosis (ALS) and multiple sclerosis, are often associated with functional gastrointestinal disorders. 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
The gut-brain axis is a bidirectional communication network functionally linking the gut and the central nervous system (CNS). 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
The aggregation of amyloid-β peptide (Aβ) has been linked to the formation of neuritic plaques, which are pathological hallmarks of Alzheimer's disease (AD). 5 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
The gut and brain form the gut-brain axis through bidirectional nervous, endocrine, and immune communications. 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
Where “Free full text” comes from
Free full text links and the Full text may need a subscription label come from Unpaywall, Europe PMC and OpenAlex records of free copies, checked 10 Oct 2026. A study with neither is unknown, not paywalled. Show only studies that are free to read
How the 0–100 score works — and why some entries are capped
This is alzhub's own score. It is not an official metric, not an impact factor, and no journal, publisher or ranking body endorses it. We built it so that a reader who is not a scientist can tell a landmark trial from a conference abstract without having to already know the difference. Every point comes from one of 20 components, all of them printed on the study itself, so you can disagree with our arithmetic rather than having to trust the total.
- Journal tier up to 10 pts
- Journal's citation record up to 4 pts
- Study design up to 12 pts
- Strength of evidence up to 5 pts
- Peer-review validation up to 10 pts
- How recent up to 5 pts
- Sample size up to 4 pts
- Effect reported up to 3 pts
- Studied in people up to 3 pts
- Randomised / blinded up to 2 pts
- Times cited up to 7 pts
- Citations per year up to 5 pts
- Impact for its field and year up to 6 pts
- Cited by studies here up to 6 pts
- Still being cited up to 4 pts
- Senior author's track record up to 4 pts
- Institution's track record up to 3 pts
- Multi-centre collaboration up to 3 pts
- Indexed in PubMed up to 2 pts
- Free to read up to 2 pts
Journals are placed in ordered tiers, never given a numeric impact factor — we could not verify current impact factors from a source we control, and an invented one would be worse than none. Tier 1 is the top-tier general journals (NEJM, The Lancet, JAMA, Nature, Science, Nature Medicine); tier 2 is the leading specialty journals; tier 3 is every other peer-reviewed journal. A separate part scores how much the journal's own papers are cited, which tells the tier-3 journals apart.
Two rules we don't bend. First, we never fill in a missing value: if a record does not state a sample size or a design, that component scores zero, and if we simply have no data for a part, such as a citation count, that part is left out and the study is scored on the parts we could check. The study card says which. Second, anything that is not a peer-reviewed article is capped at 16/100 and carries a warning chip — so a conference abstract or a company press release can never outrank a peer-reviewed paper, no matter how good it looks.
We rank a rigorous null result — a good trial showing that something does not work — above an early positive finding. Someone deciding whether to buy a supplement is served by that, and the rigour is already counted by the design and journal components.
The score is computed from the published data alone and is reproducible: the same file always yields the same numbers.
See the whole rubric drawn out → — four charts covering all 28,180 studies: how the scores are spread and where the cap bites, which of the 20 components the library is strong and weak on, which subjects rest on stronger evidence, and what kinds of study each subject is actually built from.
What this library is — and isn't
This is a large sample of the Alzheimer's literature, not an exhaustive index of it. It holds 28,180 records, built mostly from automated pulls of Europe PMC (61.7% of the library) and OpenAlex (18.1%), plus smaller pulls from PubMed, Crossref and medRxiv. If a study, a drug, or a finding isn't here, that is not evidence it doesn't exist in the literature — it may simply not have been pulled in yet.
1,034 records (3.7% of the library) are not peer-reviewed — 962 of those are preprints posted before any journal review, and the rest are conference abstracts, regulatory notices and reports. Every study card on this page states its status plainly, and the score above is capped for anything that isn't a peer-reviewed article.
See the full, machine-readable breakdown of this library's coverage →