Inflammatory bowel disease (IBD) Elevated
Adherent-invasive strains are enriched, especially in Crohn’s — a strain-level, not species-level, story.
Moderate evidence
Bacteria · Species
Escherichia coli
Associated with these conditions
Coliforms are among the bacteria that overgrow in the small intestine in hydrogen-predominant SIBO.
Preliminary
Fatty liver disease (MASLD) Elevated
Endotoxin-producing and even alcohol-producing coliforms are enriched, feeding the gut–liver inflammatory axis.
Moderate evidence
Colorectal cancer Elevated
Strains carrying the pks island produce colibactin, a genotoxin that leaves a distinctive mutational signature in colorectal tumors.
Moderate evidence
Celiac disease Elevated
Some studies find enrichment of pro-inflammatory Proteobacteria, but findings are inconsistent.
Preliminary studies conflict
Alzheimer’s disease Elevated
Pro-inflammatory Escherichia/Shigella are enriched in some cohorts and correlate with brain inflammation markers.
Preliminary
Eczema (atopic dermatitis) Elevated
Reported in HMDAD (1 cited study).
Moderate evidence
Crohn's disease(CD) Elevated
Reported in HMDAD (1 cited study).
Moderate evidence
Type 2 diabetes Associated with
Reported in Disbiome.
Preliminary
Aggressive periodontitis Associated with
Reported in Disbiome.
Preliminary
Cystic fibrosis Associated with
Reported in Disbiome.
Preliminary
Irritable Bowel Syndrome Associated with
Reported in Disbiome, Peryton.
Moderate evidence
Pervasive developmental disorder NOS Associated with
Reported in Disbiome.
Preliminary
Autism spectrum (ASD) Associated with
Reported in Disbiome.
Preliminary
Spinal cord injury Associated with
Reported in Disbiome.
Preliminary
Infectious gastroenteritis Associated with
Reported in Disbiome.
Preliminary
Hashimoto's thyroiditis Associated with
Reported in Disbiome.
Preliminary
Cardiovascular disease Associated with
Reported in Disbiome, Peryton.
Moderate evidence
Chronic kidney disease Associated with
Reported in Disbiome.
Preliminary
Pulmonary tubercolosis Associated with
Reported in Disbiome.
Preliminary
Asthma Associated with
Reported in Disbiome.
Preliminary
Hepatocellular cancer Associated with
Reported in Disbiome.
Preliminary
Ankylosing spondylitis Associated with
Reported in Disbiome.
Preliminary
Amyotrophic lateral sclerosis Associated with
Reported in Disbiome, Peryton.
Moderate evidence
Celiac Disease, Coaliac disease Associated with
Reported in Disbiome.
Preliminary
Primary liver cancer Associated with
Reported in Disbiome.
Preliminary
Breast cancer Associated with
Reported in Disbiome.
Preliminary
Atopic eczema Associated with
Reported in Disbiome.
Preliminary
Helicobacter pylori infection Associated with
Reported in Disbiome.
Preliminary
Primary sclerosing cholangitis Associated with
Reported in Disbiome.
Preliminary
Necrotizing enterocolitis Associated with
Reported in Disbiome.
Preliminary
Huntington's Disease Associated with
Reported in Disbiome.
Preliminary
Primary Open-Angle Glaucoma Associated with
Reported in Disbiome.
Preliminary
Aerobic vaginitis Associated with
Reported in Disbiome.
Preliminary
Clostridium difficile infection Associated with
Reported in Disbiome.
Preliminary
Crohn Disease Associated with
Reported in Peryton.
Preliminary
Inflammatory Bowel Diseases Associated with
Reported in Peryton.
Preliminary
Liver Neoplasms Associated with
Reported in Peryton.
Preliminary
What shifts it
Iron Raises it
Nutrient
Moderate evidence Well-established
Helps make
Dopamineneurotransmitter
Some gut bacteria synthesize dopamine directly; more importantly, they supply and modify its precursors. Dopamine itself can’t cross the blood–brain barrier, so the gut’s influence travels by other routes.
Norepinephrineneurotransmitter
This one runs conspicuously both ways: pathogens like E. coli and Salmonella SENSE host stress hormones (norepinephrine and adrenaline) as a growth signal — the bidirectional heart of the gut–brain axis, where your stress can literally feed certain microbes.
Indolesneurotransmitter
Tryptophan-derived metabolites that act as signalling molecules (including as AhR ligands), shaping the gut barrier, immune tone, and behaviour in animal models.