WikiBiomeThe human microbiome encyclopediaRanked matches across titles, topics, categories, and article introductions.
Depression is the most prevalent mental health disorder globally, affecting over 280 million people zhu 2025 microbiota gut brain axis depression review, and one of the most metal-sensitive conditions in this wiki. It sits at the convergence of nearly every pathway cata…
Postpartum depression (PPD) affects 10-20% of women after delivery, with profound consequences for maternal health, infant bonding, and child neurodevelopment chao 2025 microbiota gut brain perinatal depression. The standard framing centers on hormonal withdrawal (estro…
Probiotic supplementation targeting depleted Bifidobacterium and Lactobacillus in the postpartum period aims to restore gut-brain axis signaling disrupted during the dramatic hormonal shifts following delivery.
Harm potential: YELLOW — True iron deficiency anemia requires supplementation regardless of inflammatory state.
Allopregnanolone (3α-hydroxy-5α-pregnan-20-one) is a neurosteroid metabolite of progesterone that is the most potent endogenous positive allosteric modulator of GABA-A receptors. It is central to the pathophysiology of PMDD and postpartum depression — conditions where a…
The most common form of dementia, affecting an estimated 55 million people worldwide and projected to triple by 2050 zhang 2024 recent advances alzheimers mechanisms trials. Characterized by progressive memory loss, cognitive decline, amyloid-beta plaques, and neurofibr…
Anxiety disorders are the most prevalent mental health conditions globally, affecting ~280 million people (~4.8% of the world population). They encompass generalized anxiety disorder (GAD), social anxiety, panic disorder, and phobias. In the WikiBiome context, anxiety f…
A neurodevelopmental condition affecting approximately 1 in 36 children (US CDC 2023 estimate), characterized by differences in social communication, restricted interests, and repetitive behaviors. From a metallomics perspective, ASD presents a compelling convergence of…
A Gram-negative obligate anaerobe that exemplifies the commensal-pathobiont spectrum. B. vulgatus is a common component of the healthy gut microbiota, yet is significantly enriched in colorectal cancer and depression, suggesting a context-dependent pathogenic potential.…
BDNF is the primary neurotrophin supporting neuronal survival, synaptic plasticity, and memory formation in the hippocampus and prefrontal cortex. Reduced BDNF is a consistent finding in depression, schizophrenia, and neurodegeneration. The gut microbiome modulates BDNF…
Bipolar disorder is a chronic neuropsychiatric condition characterized by recurrent episodes of mania (or hypomania) and depression, affecting approximately 1-2.4% of the global population. It carries significant morbidity -- reduced life expectancy by 10-15 years, high…
Cardiovascular disease (CVD) -- encompassing atherosclerosis, coronary artery disease, hypertension, myocardial infarction, heart failure, and stroke -- is the leading cause of death globally. The gut-heart axis has emerged as a central paradigm linking microbial metabo…
The major copper-carrying protein in human blood, binding approximately 95% of circulating copper. Ceruloplasmin is far more than a passive transport vehicle -- it is a multicopper oxidase with ferroxidase activity, an acute-phase reactant that rises with inflammation, …
The co-occurrence of multiple diseases in the same individual at rates exceeding chance. Comorbidity patterns are a central puzzle in medicine -- why do IBD patients develop CVD? Why does PCOS cluster with T2D? Why do neurodegenerative diseases associate with depression…
Perhaps the most pervasive metallomic finding across human disease: copper is elevated in nearly every pathological condition examined in this wiki -- cancer (pan-cancer), PCOS, cardiovascular disease, depression, schizophrenia, IBD, and rheumatoid arthritis. Simultaneo…
A Gram-positive, obligate anaerobic genus within the lachnospiraceae family (Firmicutes phylum). Coprococcus is one of the most important butyrate-producing commensals in the human gut and has gained particular attention as the "happiness bug" -- one of very few taxa di…
Cortisol is the primary glucocorticoid stress hormone, produced by the adrenal cortex under HPA (hypothalamic-pituitary-adrenal) axis control. In the WikiBiome framework, cortisol is the molecular bridge between psychological stress and microbiome disruption — it direct…
A chronic, relapsing-remitting inflammatory bowel disease (IBD) characterized by transmural inflammation of the gastrointestinal tract, most commonly affecting the terminal ileum and colon but capable of involving any segment from mouth to anus zhang 2017 intestinal mic…
Dialister is a genus of Gram-negative, obligate anaerobic bacteria within the family Veillonellaceae that represents one of the strongest protective associations in gut-brain-axis research. Dialister depletion is a consistent and independent biomarker of depression, anx…
Epilepsy is a chronic neurological disorder characterized by recurrent unprovoked seizures, affecting ~50 million people worldwide. Approximately 30% of patients have drug-resistant epilepsy -- a population where microbiome-targeted interventions (particularly the ketog…
Erectile dysfunction (ED) affects 30-50% of men aged 40-70 Feldman et al. 1994, with prevalence increasing with age. Conventionally understood as a vascular and/or neurogenic disorder, ED is now recognized as a condition with a significant gut microbiome component -- th…
Fibromyalgia (FM) is a chronic pain syndrome affecting 2-4% of the global population Heidari et al. 2017, characterized by widespread musculoskeletal pain, fatigue, cognitive dysfunction ("fibro fog"), and sleep disturbances. Conventionally attributed to central sensiti…
Gamma-aminobutyric acid (GABA) is the primary inhibitory neurotransmitter in the central nervous system. In the WikiBiome context, GABA is notable because gut bacteria produce it — certain Lactobacillus and Bifidobacterium species possess glutamate decarboxylase (GAD) e…
Alphabetical definitions of specialist terms used throughout this wiki. Where a full concept page exists, the term links to it. --- AhR (aryl hydrocarbon receptor) -- A ligand-activated transcription factor that senses microbial metabolites (especially indoles from tryp…
Bidirectional communication between the gut microbiota and the central nervous system, mediated by neural (vagus nerve, enteric nervous system), immune (cytokines, microglia), endocrine (HPA axis), and metabolic (SCFAs, neurotransmitter precursors, tryptophan metabolite…
A genus of Gram-positive, strictly anaerobic bacteria in the family Erysipelotrichaceae (phylum Firmicutes) that is emerging as one of the most consistently protective gut commensals in human disease. Holdemanella is depleted across a striking range of conditions -- inf…
IL-8 (CXCL8) is the primary neutrophil chemokine — it recruits neutrophils to infection sites and activates their antimicrobial functions (oxidative burst, degranulation, NET formation). In the WikiBiome context, IL-8 is notable for its vulnerability to gingipain degrad…
Interleukin-6 is a pleiotropic cytokine that sits at the crossroads of innate immunity, adaptive immunity, and metabolism. It is one of the most frequently elevated inflammatory mediators across conditions in this wiki — appearing in disease signatures spanning IBD, aut…
The most abundant transition metal in the human body and arguably the most consequential metal in biology. Iron sits at the center of a paradox that drives pathology across virtually every disease domain: organisms need it for oxygen transport, energy metabolism, DNA sy…
Research summary — not medical advice. This page synthesizes published research on a mechanism-level intervention. It is not a clinical recommendation. Consult a qualified healthcare provider before making any changes to diet, supplementation, or treatment.
The kynurenine pathway (KP) is the dominant route of tryptophan catabolism, accounting for approximately 95% of dietary tryptophan degradation. It produces a cascade of neuroactive, immunomodulatory, and potentially neurotoxic metabolites whose balance determines whethe…
Lead is a purely toxic heavy metal with no known biological function. It is the most extensively studied metal in relation to neurodevelopmental harm and is increasingly recognized as a contributor to chronic disease across virtually every organ system, even at levels o…
An essential macromineral required as a cofactor for over 300 enzymatic reactions in the body, including energy metabolism, protein synthesis, DNA/RNA stability, and neuromuscular function. Magnesium is not a heavy metal or trace element but is frequently measured along…
Major depressive disorder (MDD) is a psychiatric condition characterized by persistent depressed mood, anhedonia, and cognitive/somatic symptoms. In the WikiBiome framework, MDD is a paradigm case for the gut brain axis: gut dysbiosis drives systemic inflammation and ne…
The Mediterranean diet demonstrated broad symptomatic improvement in fibromyalgia across multiple domains in an RCT (n=84), including pain, disability, fatigue, anxiety, and depression at 2 months.
Mercury is the most toxic heavy metal with no known biological function. Its organic form -- methylmercury (MeHg) -- is the primary concern for dietary exposure via fish consumption. Mercury's toxicity centers on thiol group binding, glutathione depletion, and blood-bra…
A class of bacteria within the phylum Tenericutes defined by the complete absence of a cell wall -- the smallest self-replicating organisms known, with minimal genomes (580 kb-1.4 Mb). While Mollicutes are best known through their pathogenic members (Mycoplasma pneumoni…
A transition metal occupying a central position in this wiki's evidence base. Nickel is toxic and carcinogenic to humans, yet an essential cofactor for pathogen virulence enzymes. It is the most frequent contact allergen worldwide and drives a wide spectrum of systemic …
Chronic nickel exposure can damage the central nervous system, causing behavioral and cognitive deficits through oxidative stress in the hippocampus and disruption of multiple neurotransmitter systems.
The second most common neurodegenerative disease, affecting over 10 million people worldwide dorsey 2018 parkinsons incidence meta analysis. Characterized by progressive loss of dopaminergic neurons in the substantia nigra, alpha-synuclein aggregation (Lewy bodies), and…
Premenstrual Dysphoric Disorder (PMDD) affects 3-8% of menstruating individuals Epperson et al. 2012, causing severe mood disturbances, irritability, anxiety, and physical symptoms during the luteal phase of the menstrual cycle. Distinguished from premenstrual syndrome …
A family of Gram-negative, obligate anaerobic bacteria within the phylum Bacteroidota (formerly Bacteroidetes) that includes the genus prevotella and the recently described alloprevotella. Prevotellaceae are specialist fiber fermenters producing short-chain fatty acids,…
Psoriasis is a chronic, immune-mediated inflammatory skin disease characterized by keratinocyte hyperproliferation, resulting in well-demarcated erythematous plaques with silvery scales. Affecting approximately 2-3% of the global population, psoriasis is now understood …
Quinolinic acid (QA) is a neurotoxic metabolite of the kynurenine pathway — the branch of tryptophan catabolism driven by IFN-γ-induced IDO activation. QA is an NMDA receptor agonist that causes excitotoxic neuronal death at elevated concentrations. It is produced prima…
A Gram-positive obligate anaerobe that has emerged as a pro-inflammatory pathobiont enriched across multiple disease states including crohns disease, depression, and multiple sclerosis. R. gnavus produces a species-specific inflammatory polysaccharide that activates int…
An essential trace element that is primarily protective in its biological roles. Unlike most metals in this wiki, selenium's toxicological significance lies more in the consequences of its deficiency than its excess. Selenium is the backbone of the selenoproteome -- a f…
The serotonin-estrogen axis describes the bidirectional relationship between estrogen signaling and serotonin (5-HT) neurotransmission — a neuroendocrine interface that is profoundly modulated by the gut microbiome. Estrogen regulates serotonin synthesis (via tryptophan…
Zinc is depleted in nearly every disease state examined in this wiki -- cancer (breast, prostate, lung, pancreatic, esophageal, colorectal), type 2 diabetes, PCOS, autism, postpartum depression, and IBD. Zinc supplementation is generally beneficial: it reduces PPD risk …
Tryptophan (Trp) is an essential amino acid metabolized via three competing pathways: the kynurenine pathway, the serotonin pathway, and the microbial indole pathway. The balance among these pathways is profoundly influenced by the gut microbiome, inflammation, and meta…
Type 2 diabetes (T2D) is a metabolic disease characterized by insulin resistance and progressive beta-cell dysfunction, affecting over 500 million people worldwide (IDF Diabetes Atlas 2021). The conventional framing centers on caloric excess and sedentary behavior. The …
Tyzzerella is a genus of Gram-positive, strictly anaerobic bacteria within the family Lachnospiraceae (order Clostridiales, phylum Firmicutes). It was recently reclassified from Clostridium cluster XIVa and remains poorly characterized at the species level. The genus in…
Vitamin D (calciferol; active form: calcitriol/1,25(OH)₂D₃) is a secosteroid hormone with profound immunomodulatory effects. The vitamin D receptor (VDR) is expressed on virtually all immune cells, and vitamin D deficiency is epidemiologically linked to autoimmune disea…
Zinc is the most widely utilized transition metal cofactor in biology. Approximately 9-10% of the eukaryotic proteome and 5-6% of the bacterial proteome consists of zinc-binding proteins capdevila 2024 bacterial metallostasis sensing trafficking. An estimated one-third …