Cross-sectional studyindependent cross-checkabstract checked I-SRC-123 standard review
Tea drinking and reflux in Taiwan
Habitual tea consumption is associated with a low prevalence of gastroesophageal reflux disease in a Taiwanese population study.
Overview
Kuo CM et al.. Int J Med Sci 2026 · PMID 42807308 · DOI 10.7150/ijms.139922
Habitual drinkers of green or oolong tea had somewhat less reflux; black tea showed no link.
Does the study support the specific claim? No · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Test tea and reflux
- How was the study done?
Cross-sectional study
- How many people, animals or samples were studied?
27,119 adults
- What was actually found?
Lower reflux with green/oolong tea; black tea neutral
- How large was the observed effect?
OR 0.843
- What do the results mean in everyday life?
Tea does not generally cause reflux
- What are the study's limitations?
Self-report; tea types differ
- What does it say about Elawady's specific claim?
Contradicts the claim
- Do the results apply to Germany and Europe?
Low
- What can explicitly not be concluded from this study?
Causation
Scientific in-depth review
1. Full reference
- Authors
- Kuo CM et al.
- Journal
- Int J Med Sci
- Year
- 2026
- Identifier
- PMID 42807308 DOI 10.7150/ijms.139922
- Verification
- verified – PubMed efetch 2026-10-26; Crossref works record checked
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
No competing interests.
2. Research question
Is habitual tea consumption associated with GERD?
3. Study design and population
- Study design
- Cross-sectional study – Cross-sectional analysis of a large Taiwanese population cohort
- Population
Taiwanese adults
- Country
Taiwan
- Period
Published 2026
- Sample size
27,119 (4706 with GERD)
- Inclusion and exclusion criteria
Participants with questionnaire data
4. Methods and endpoints
- Exposure / intervention
Tea type, frequency, amount
- Comparator
Non-drinkers
- Endpoints
Self-reported GERD
- Statistical methods
Multivariable logistic regression
5. Actual results
- Results
Habitual tea drinking associated with lower GERD prevalence (OR 0.843, 0.779-0.911); only semi-/non-fermented tea (OR 0.832, 0.765-0.905), not fully fermented tea; 1-2 cups/day associated (OR 0.881 and 0.765); >3 cups/day not significant.
- Absolute risks
GERD prevalence 17.4% overall.
- Authors' conclusion
Semi- and non-fermented tea was associated with lower GERD prevalence depending on amount and frequency.
6. Strengths
- Large sample
7. Weaknesses
- Cross-sectional; self-reported GERD
- Mostly green/oolong tea, unlike Egyptian black tea
- Fully fermented (black) tea not associated
8. Risk of bias
- Orienting tool
- ROBINS-E
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Reverse causation possible (people with reflux may avoid tea).
9. Assessment of the statistical interpretation
CI log-symmetric; association only.
10. Relevance to the specific claim
Contradicts a general reflux-causing effect of tea; for black tea (Egyptian habit) there was no association either way.
11. Independent contrary findings
I-INTA-01 (East Asian subgroup OR 1.27).
12. Transferability to Germany and Europe
Low transferability (tea type).
13. Overall methodological judgement
Adds to mixed, mostly null evidence.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | high |
| Directness | indirect |
| Reproducibility | unknown |
| Consistency with the overall evidence | mixed |
| Regional transferability | low |
| Adequacy of the interpretation (by the archive) | not applicable |