SIBO Through the Host Capacity Model
Why SIBO recurs: a habitat-based reframe of small intestinal bacterial overgrowth using the Host Capacity Model.
Recurrent SIBO is best understood as a habitat problem: motility, oxygen tension, bile acid pool, and bioenergetic capacity all shape whether bacteria can colonize the small intestine.
At a glance
Short answer
Recurrent SIBO is best understood as a habitat problem: motility, oxygen tension, bile acid pool, and bioenergetic capacity all shape whether bacteria can colonize the small intestine.
Mechanistic summary
Host capacity loss → MMC weakening + bile acid pool shift + mucosal immune dampening → small bowel becomes hospitable → bacterial expansion proximal to its normal niche → fermentation symptoms → breath test signal → antibiotic kill → habitat unchanged → recurrence.
Key concepts
- SIBO Through the Host Capacity Model
- The Host Capacity Model
- Bile Acid Dysfunction
- Dysbiosis as Ecological Adaptation
Evidence status
Mechanistic inference. Synthesis of motility, bile, and ecology literature applied to clinical SIBO recurrence.
Definition
Small Intestinal Bacterial Overgrowth (SIBO) reframed as the predictable ecological output of host habitat changes — disrupted MMC motility, altered bile acid antimicrobial pressure, mucosal immune dysfunction, and proximal oxygen-gradient changes.
Mechanism
Host capacity loss → MMC weakening + bile acid pool shift + mucosal immune dampening → small bowel becomes hospitable → bacterial expansion proximal to its normal niche → fermentation symptoms → breath test signal → antibiotic kill → habitat unchanged → recurrence.
Recurrent SIBO is best understood as a habitat problem: motility, oxygen tension, bile acid pool, and bioenergetic capacity all shape whether bacteria can colonize the small intestine. Why SIBO recurs: a habitat-based reframe of small intestinal bacterial overgrowth using the Host Capacity Model.
Frequently asked questions
- Why does SIBO keep coming back?
- Because antimicrobials kill organisms but do not restore the host conditions (motility, bile, capacity) that prevent recolonization.
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Related concepts
Mechanistic intelligence
This concept is rated evolving based on 1 linked claim and 1 active contradiction.
This concept appears in 3 causal chains: Bile-acid pool failure → proximal small-bowel overgrowth; (Competing) Motility failure → stagnation → microbial overgrowth → barrier stress; (Competing) SIBO + MCAS as independently co-occurring, not shared-driver.
1 unresolved contradiction touches this concept: Are lactulose / glucose breath tests a valid diagnostic for SIBO?
- Oxygen Gradient FailureWhen colonocyte mitochondria stop consuming oxygen, the colonic lumen becomes oxygenated, obligate anaerobes die off, and facultative pathobionts expand.
- The Host Capacity ModelThe Host Capacity Model (HCM) reframes chronic gut and post-viral illness as downstream consequences of colonocyte bioenergetic failure, not primary microbial pathology.
- Bile Acid DysfunctionBile acids are not just lipid emulsifiers — they are antimicrobial signaling molecules whose pool composition shapes microbial ecology and host metabolism.
Educational disclaimer. This page is educational and informational only. It is not medical advice, diagnosis, or treatment. Consult a qualified clinician for personal health decisions.