Counterargument
What if normal stool testing does not exclude mucosal dysfunction?
Stool tests have meaningful blind spots: mucosal-adherent communities, small-bowel content, and mucosal metabolic state may not be captured.
Where it is valid
All stool-based microbial assays. Normal stool ≠ normal mucosa.
What it challenges
Over-reliance on stool testing to confirm or exclude HCM-relevant dysfunction.
Host Capacity Model response
HCM is consistent with this limitation. The framework explicitly does not require abnormal stool testing to consider host-capacity context, and treats stool data as one input among many.
Unresolved questions
- What non-stool signals best approximate mucosal bioenergetic state in clinical practice?
Evidence that would resolve this
- Validation of mucosal biopsy or breath-based proxies for colonocyte bioenergetic state.