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
13 articles · recurrent SIBO
Mast-cell activation, tryptase & histamine
17 articles · mast cell activation
Long COVID, post-viral gut–immune & POTS
12 articles · Long COVID gut symptoms
Colonocyte bioenergetics, butyrate & oxygen
18 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
5 articles · lab pattern interpretation
6 articles
- Case Reasoning· August 3, 2026· 12 min· Clinical pattern observation
The Microbial Metabolites That May Be Rewiring the Brain: The Hidden Link Between SIBO, IBS, MCAS, Autism, ADHD, Glutamate, and Catecholamine Dysfunction
HPHPA, hydrogen sulfide, D-lactate and ammonia are microbial metabolites that may pressure catecholamine regulation through dopamine β-hydroxylase, COMT and mitochondrial ATP. A case-anchored look at the hidden link between SIBO, IBS, MCAS, POTS, ADHD-like symptoms and autism-spectrum features — a metabolite-driven mechanism rather than a purely compositional dysbiosis.
#hphpa#clostridia#dopamine-beta-hydroxylase - 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 - SIBO· April 11, 2026· 10 min· Mechanistic inference
Your SIBO Subtype Doesn't Matter — Until You Fix the Cell That Created It
Hydrogen, methane and hydrogen sulfide describe which organisms expanded, not why the terrain allowed it. Why subtype-directed treatment keeps failing when the upstream epithelial failure is untouched.
#sibo#hydrogen#methane - SIBO· March 31, 2026· 22 min· Mechanistic inference
SIBO Breath Test Accuracy: Why Hydrogen, Methane, and Hydrogen Sulfide Don’t Reliably Diagnose Small Intestinal Bacterial Overgrowth
A detailed examination of what hydrogen, methane and hydrogen sulfide breath curves can and cannot establish about small intestinal bacterial overgrowth, including transit confounding, substrate choice and threshold arbitrariness.
#sibo-breath-test#lactulose#glucose - SIBO· March 30, 2026· 11 min· Mechanistic inference
Hydrogen Sulfide, Serotonin Control, and Why Gut Motility Becomes Unstable
Serotonin in the gut is a control signal, not a mood molecule. How excess microbial hydrogen sulfide can disturb serotonin handling and make motility unstable in both directions.
#hydrogen-sulfide#serotonin#5-ht
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