CHAMGAP
APPROVEDReviewed and approved by the Chamgap Editorial Team (2026-08-15). The draft was written by AI, the existence of all 1 cited sources was verified at the original page, and the verdict passed blind grading and adversarial audit. Methodology v0.7.
Verdict No. 2677 · Search date 2026-08-15 · Methodology v0.7

Abdominal breathing training,
does it really help with Reduced esophageal acid exposure in gastroesophageal reflux disease?

30-Second Summary
C
Evidence Grade C · 46 · Safety acceptable
Abdominal breathing showed an acid-exposure signal, but the very small trial did not report a recoverable between-group magnitude
No major harm signal from abdominal breathing was reported. Stop if dizziness or hyperventilation occurs, and seek care for alarm symptoms or medication decisions.
What the
research shows
The grade is C with 46 points. In an open 19-person randomized trial, the training group reduced time with esophageal pH below 4 from 9.1% to 4.7% after four weeks, but public material does not provide control-group values or an adjusted between-group difference and confidence interval. This was a physiologic surrogate in a very small single trial with an unreconstructable treatment-effect magnitude.
What the
ads claim
A physiologic explanation about diaphragm recruitment does not establish symptom benefit. The randomized primary result concerned four-week acid exposure, while long-term medication reduction was not randomized.
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Useful facts when choosing a product

  • The intervention trained a shift from thoracic to abdominal breathing for four weeks.
  • UMIN000004878 was registered after the trial began.
  • Both groups were offered training after four weeks, ending the randomized comparison.
Gap Measurement · Verdict 2677 · C 46
What advertising claims
What independent, higher-quality research supports
△ GAP
01

What the research actually shows

Nineteen participants were assigned 10 to training and 9 to control, and all completed four weeks. Time with pH below 4 fell from 9.1±1.3% to 4.7±0.9% within the training group, while the control group had no significant within-group change. Comparing significance with nonsignificance does not itself prove a between-group difference. The public abstract and registry omit both control values, the between-group change estimate, its standard error or confidence interval, and a between-group test statistic, so a standardized treatment effect cannot be reconstructed. At nine months, 11 voluntary continuers were compared with eight noncontinuers after both randomized groups had been offered training. Registration occurred after trial initiation, and assessor masking, concealment implementation, assignment-based analysis, and missing-data handling were not reported.

02

Why this is classified as C (46)

A 19-person open, retrospectively registered single trial measured a surrogate and omitted the recoverable between-group effect magnitude, giving C with 46 points.

Counterpoint. Dyspnea, chest pain, dysphagia, bleeding, or weight loss requires medical assessment, and prescribed acid suppression should not be stopped without clinical advice.

Rejudgment record. Cross-check applied — Cross-checked the abstract, UMIN000004878, and a later randomized trial for the primary endpoint, denominators, retrospective registration, and absent between-group effect estimate

Scoring profile behind this grade
EndpointSSurrogate marker - laboratory or imaging measures
ReplicationR1Single confirmatory trial
IndependenceI1Mixed funding sources
Effect sizeEXThe clinical size of the effect could not be judged

The scoring table and the verdict agree (C).

Sub-claim grades by effect

This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.

Effect (sub-claim)GradeBasis
Reduced esophageal acid exposure at four weeksCThe within-training-group reduction was positive, but the between-group magnitude cannot be reconstructed.
Reduced PPI use at nine monthsCThe comparison of voluntary continuers with noncontinuers was no longer randomized.

Cross-check — Codex and Claude

This verdict was drafted by Codex through literature review and source-existence checks, cross-checked through blind grading and adversarial audit, and settled by reapplying the methodology boundary rules. Cases with split grades were resolved through rejudgment.
03

Evidence Table

StudyDesignSampleFundingEndpointResultWeight
Eherer AJ, Netolitzky F, Högenauer C, Puschnig G, Hinterleitner TA, Scheidl S, Kraxner W, Krejs GJ, Hoffmann KM. 2012Single-center open-label parallel-group randomized trial8Registry listed no external funding; the paper's Funding and Disclosure statements could not be confirmedFraction of esophageal recording time with pH below 4 at four weeksTraining group 9.1±1.3% to 4.7±0.9%, P<0.05; control values, between-group change, and CI unavailableVery small physiologic surrogate trial with unreconstructable treatment-effect magnitude
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Receipt — 1 References

All 1 cited sources were verified for existence at the original page (as of 2026-08-15).

Eherer AJ, Netolitzky F, Högenauer C, Puschnig G, Hinterleitner TA, Scheidl S, Kraxner W, Krejs GJ, Hoffmann KM. Positive effect of abdominal breathing exercise on gastroesophageal reflux disease: a randomized, controlled study. Am J Gastroenterol. 2012;107(3):372-378. PMID: 22146488. DOI: 10.1038/ajg.2011.420. UMIN000004878.
checked
Draft and rewrite: Codex (AI) · Verification: Codex blind grading and adversarial audit · Final adjudication: Claude
Reviewed and approved: Chamgap Editorial Team · Approval date: 2026-08-15 · Corrections: none

Cite this verdict

Abdominal breathing training x reduced gastroesophageal reflux Evidence Grade C card
[Chamgap] Abdominal breathing training x reduced gastroesophageal reflux — Evidence Grade C·46. 1 cited sources checked. Source: https://chamgap.com/en/verdicts/gut/abdominal-breathing-training-gastroesophageal-reflux/ · CC BY 4.0

CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.

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