The limits are published alongside the reasoning.
- Evidence tiers
Every article carries an explicit evidence tier, so established biology is never presented as if it were clinical proof.
Read the claim ledger - What this does not prove
Mechanistic pieces are required to state their own limits and the competing explanations that would fit the same data.
See the counterarguments - Published corrections
Where the reasoning has been revised, the revision is recorded rather than quietly edited away.
Review the standards
Pick the sentence that sounds like your situation.
- Why does my SIBO keep coming back?
- Are SIBO breath tests actually reliable?
- Why don't antihistamines settle my symptoms?
- Can I have mast cell activation with normal tryptase?
- Why won't my Long COVID symptoms resolve?
- Why did COVID trigger this in me and not others?
- Why are my labs normal when I feel terrible?
- Why doesn't my stool test match my symptoms?
- Why does every protocol stop working after two weeks?
- Why did butyrate or probiotics make me worse?
- What do bile acids have to do with my gut symptoms?
- Can gut health affect my hormones and egg quality?
Educational mechanistic writing. It does not diagnose, and it does not replace the clinician treating you.
Seven mechanistic threads run through this library.
Recurrent SIBO & breath-test interpretation
14 articles · recurrent SIBO
Mast-cell activation, tryptase & histamine
19 articles · mast cell activation
Long COVID, post-viral gut–immune & POTS
13 articles · Long COVID gut symptoms
Colonocyte bioenergetics, butyrate & oxygen
19 articles · colonocyte bioenergetics
Bile acids, TUDCA & C. difficile ecology
5 articles · bile acid dysfunction
Gut–hormone axis, fertility & estrobolome
3 articles · gut microbiome and fertility
Lab-pattern interpretation
6 articles · lab pattern interpretation
11 articles
- Case Reasoning· July 29, 2026· 32 min· Clinical pattern observation
What a Two-Decade Steroid-Dependent IBD Case Revealed About Redox Collapse, Malabsorption, Microbial Instability, and Host Capacity
A man in his forties with two decades of steroid-dependent inflammatory bowel disease was taking four grams of vitamin C daily — and his ascorbate marker sat near the bottom of the range. That contradiction opened a full mechanistic case analysis of redox collapse, fat malabsorption, microbial instability, and host capacity.
#case-study#ibd#crohns - Host Capacity Model· June 11, 2026· 28 min· Mechanistic inference
Why Dysbiosis, SIBO, Hydrogen Sulfide Intolerance, MCAS, and Long COVID May All Be Downstream of a Single Event
Dysbiosis, SIBO, hydrogen sulfide intolerance, MCAS, and long COVID may all be downstream of one event: the colonocyte losing control of oxygen, butyrate, and its own mitochondria. The Host Capacity Model in full.
#host-capacity-model#colonocyte#butyrate - Mitochondria· May 25, 2026· 5 min· Mechanistic inference
Ulcerative Colitis Starts in the Mitochondrion
For forty years the field treated UC as immune dysregulation. The 2024 and 2025 literature finally admits what was upstream all along.
#ulcerative-colitis#ibd#mitochondria - Host Capacity Model· May 14, 2026· 12 min· Mechanistic inference
The Mycotoxin-Mitochondria Trap: Why Standard Detox Fails in Chronic Illness, and How to Escape It
Mycotoxins directly impair mitochondrial function and disrupt the gut oxygen gradient, creating a bioenergetic trap that binders alone cannot break. A Host Capacity Model interpretation of why standard detox protocols fail in SIBO, MCAS, and long COVID, and what the upstream lesion actually requires.
#mycotoxins#mitochondria#colonocyte-bioenergetics - Host Capacity Model· May 14, 2026· 14 min· Mechanistic inference
Beyond Weight Loss: How GLP-1 Agonists Influence Gut Bioenergetics and the Host Capacity Model
Emerging research suggests GLP-1 receptor agonists do more than regulate glucose and appetite. They also influence colonocyte mitochondrial function, the gut oxygen gradient, the microbiome, and barrier integrity, with direct relevance to the Host Capacity Model.
#glp-1#semaglutide#colonocyte-bioenergetics - Host Capacity Model· May 14, 2026· 32 min· Mechanistic inference
Why Your Chronic Illness Got Dramatically Worse in Perimenopause: The Hormonal Cascade Driving Gut, Mast Cell, Brain Fog, and Fatigue Symptoms in Your 40s
What the research now shows about why women in their 40s experience the emergence or sudden worsening of MCAS, histamine intolerance, SIBO, autoimmune flares, and post viral illness, and where the actual upstream lesion lives.
#perimenopause#mcas#histamine - Host Capacity Model· May 14, 2026· 30 min· Mechanistic inference
Why Your Brain Fog Won't Lift: The Six Mechanisms of Cognitive Dysfunction in Chronic Illness, and Why Standard Interventions Keep Failing
What patients with persistent brain fog across long COVID, MCAS, SIBO, perimenopause, and ME/CFS have in common, and where the actual lesion lives.
#brain-fog#long-covid#mcas - Host Capacity Model· May 14, 2026· 28 min· Mechanistic inference
Why hEDS, POTS, and MCAS Almost Always Come Together: The Mechanistic Triad and the Upstream Lesion Standard Medicine Doesn't Treat
Why hEDS, POTS, and MCAS cluster as one integrated illness — three faces of a structural vulnerability decompensating against a shared bioenergetic capacity ceiling.
#heds#pots#mcas - Host Capacity Model· May 14, 2026· 32 min· Mechanistic inference
Why Long COVID May Not Resolve: A Mechanistic Reading of Viral Persistence, Mitochondrial Dysfunction, and the Gut–Brain Axis the Standard Model Is Missing
What three years of research actually shows about viral persistence, serotonin depletion, mitochondrial impairment, microclots, and EBV reactivation — and a candidate upstream layer that may tie them together.
#long-covid#mitochondria#viral-persistence - Mitochondria· May 11, 2026· 7 min· Mechanistic inference
Incomplete Autophagy and the Long COVID Lock-In: A Mechanistic Lens
I keep stumbling into the same intersection from different directions. For the last few weeks I’ve been pulling on a thread that started innocently — a question about why some post-COVID patients respond dramatically to extended fasting while others crash. The literature on SA…
#long-covid#autophagy#mitophagy - MCAS & Mast Cells· April 11, 2026· 27 min· Mechanistic inference
Your Mast Cells Have a Mitochondrial Problem: The Genetic and Metabolic Layer Nobody Tested For
Mast cell degranulation is an energy-dependent event. A long-form look at the mitochondrial, genetic and metabolic layer that determines how easily a mast cell fires — and why it is rarely tested.
#mast-cells#mitochondria#mtdna
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