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
22 articles · showing 12
- Case Reasoning· August 18, 2026· 24 min· Clinical pattern observation
Long COVID, Candida, and Klebsiella: When the Gut Loses Its Ecological Control
Post-COVID cases repeatedly show loss of ecological control rather than a single pathogen: Candida and Klebsiella expansion as a readout of failed colonization resistance. What that pattern implies for interpretation rather than eradication.
#long-covid#post-viral#candida - Frameworks· August 17, 2026· 9 min· HCM interpretation
How Bile Acids Suppress C. difficile and Why the Same Chemistry Can Harm the Host
The same bile-acid chemistry that suppresses C. difficile germination can injure the host epithelium at higher exposure. A dose- and context-dependent reading of bile-acid ecology rather than a good/bad framing.
#bile-acids#c-difficile#secondary-bile-acids - MCAS & Mast Cells· August 6, 2026· 4 min· Mechanistic inference
Your Mast Cells May Be Reacting to a Gut That Never Stopped Signaling Danger
Mast cells rarely become reactive without an input. A short reading of the gut-derived signalling that keeps them primed, and why that reframes mast-cell symptoms as downstream rather than primary.
#mast-cells#mcas#dysbiosis - Host Capacity Model· August 5, 2026· 6 min· Mechanistic inference
Why Dysbiosis Keeps Coming Back: The Overlooked Vitamin B2–Butyrate–Oxygen Connection
Riboflavin sits in the electron-transfer chemistry that lets colonocytes burn butyrate and hold the colon hypoxic. A mechanistic account of why dysbiosis recurs when that oxygen-consuming step is limited.
#riboflavin#vitamin-b2#butyrate - 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 - MCAS & Mast Cells· July 17, 2026· 28 min· Mechanistic inference
Rethinking Chronic Dysbiosis, Mast Cell Activation, and the Failure of Intestinal Ecological Control
Why the microbiome may remain unstable until the intestinal epithelium regains the capacity to metabolize microbial products, consume oxygen, regulate inflammation, and rebuild itself
#dysbiosis#mast-cells#mcas - 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 - MCAS & Mast Cells· June 9, 2026· 13 min· Mechanistic inference
Why Mast Cell Activation May Be the Last Domino, Not the First — A Systems-Biology Reframe of MCAS
For decades, the mast cell has carried a reputation it may not fully deserve. We learned it as the cell of allergy: the histamine grenade, the hive, the wheeze, the anaphylactic emergency. In that framing, Mast Cell Activation Syndrome (MCAS) becomes a straightforward story —…
#mcas#mast-cells#systems-biology - SIBO· May 25, 2026· 16 min· Mechanistic inference
Why Does SIBO Keep Coming Back After Treatment?
Recurrent SIBO may represent an equilibrium state of an unaddressed host substrate failure. Antimicrobials reduce overgrowth without restoring the colonocyte bioenergetic capacity that defines which microbes can dominate. A Host Capacity Model reading of the recurrence cycle, the SLC5A8 / Fe-S / CD38-NAD+-SIRT3 mechanisms behind it, and what an HCM-anchored approach actually looks like.
#sibo#recurrent-sibo#host-capacity-model - Host Capacity Model· May 21, 2026· 23 min· Mechanistic inference
Why Probiotics Make You Sicker, Not Better: The Six Mechanisms Driving Probiotic Failure in MCAS, SIBO, Histamine Intolerance, and Long COVID, and Why The Field Has Been Asking The Wrong Question
What the research actually shows about why patients with chronic gut dysfunction react badly to the most widely recommended supplement in functional medicine, and where the actual lesion lives.
#probiotics#histamine#d-lactate - Host Capacity Model· May 14, 2026· 25 min· Mechanistic inference
Why Your Stool Test Doesn't Match Your Symptoms: The Mechanistic Limits of GI-MAP, BiomeFx, and Comprehensive Stool Analysis
What GI-MAP, BiomeFx, Genova, and comprehensive stool panels actually measure, what they cannot, and how to read your own gut when the report falls short.
#stool-testing#gi-map#biomefx - Fertility· May 8, 2026· 4 min· Literature-supported mechanism
How Dysbiosis Disrupts Hormonal Health, Ovulation, and Egg Quality From the Inside Out
The fertility conversation has become overwhelmingly hormone-centric, but one of the most important mechanistic layers is still being underappreciated: the inflammatory dialogue between the gut microbiome and the ovary itself.
#butyrate#dysbiosis#lps
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