People with constipation who stopped eating fiber completely stopped having blood in their stool, while those who kept eating fiber still had bleeding.
Scientific Claim
In adults with idiopathic constipation, complete elimination of dietary fiber for six months is associated with the complete resolution of anal bleeding, while those continuing high fiber intake continue to experience bleeding.
Original Statement
“None of our patients experienced anal bleeding ... following complete abstinence from dietary fiber. ... Anal bleeding was present in 4 of 6 patients on high fiber diet at 6 mo (P < 0.001).”
Evidence Quality Assessment
Claim Status
overstated
Study Design Support
Design cannot support claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The claim implies a direct effect, but the study design cannot rule out confounding variables. The association is clear, but causation cannot be established.
Evidence from Studies
Supporting (1)
People with chronic constipation who stopped eating fiber had way less straining and discomfort, while those who kept eating fiber still had problems—suggesting cutting fiber helped stop bleeding caused by straining.