Cross-sectional studyindependent cross-checkabstract checked★ key study I-FSH-116 standard review
Shellfish allergy affects about 3 in 100 US adults
Prevalence and Severity of Food Allergies Among US Adults.
Overview
Gupta RS et al.. JAMA Netw Open 2019 · PMID 30646188 · DOI 10.1001/jamanetworkopen.2018.5630
Shellfish was the most common adult food allergy, at 2.9%.
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?
Estimate adult food allergy.
- How was the study done?
Survey of 40,443 adults.
- How many people, animals or samples were studied?
US adults.
- What was actually found?
Shellfish allergy 2.9%.
- How large was the observed effect?
2.9% (2.7-3.1%).
- What do the results mean in everyday life?
Most people tolerate shellfish.
- What are the study's limitations?
Self-report.
- What does it say about Elawady's specific claim?
Contradicts 'most people'.
- Do the results apply to Germany and Europe?
Moderate.
- What can explicitly not be concluded from this study?
Prevalence in Egypt.
Scientific in-depth review
1. Full reference
- Authors
- Gupta RS et al.
- Journal
- JAMA Netw Open
- Year
- 2019
- Identifier
- PMID 30646188 DOI 10.1001/jamanetworkopen.2018.5630
- Verification
- verified – PubMed efetch 2026-10-26; Crossref checked
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
NIH extramural support
2. Research question
How common are food allergies among US adults?
3. Study design and population
- Study design
- Cross-sectional study – Nationally representative cross-sectional survey
- Population
US adults
- Country
USA
- Period
2015-2016
- Sample size
40,443
4. Methods and endpoints
- Exposure / intervention
Food allergens
- Endpoints
Convincing (symptom-based) food allergy
- Statistical methods
Weighted prevalence with 95% CI
5. Actual results
- Results
Convincing food allergy 10.8% (95% CI 10.4-11.1%); most common: shellfish 2.9% (2.7-3.1%), milk 1.9%, peanut 1.8%, tree nut 1.2%, fin fish 0.9% (0.8-1.0%). 19.0% self-reported a food allergy.
- Absolute risks
Shellfish allergy in 2.9% of adults (about 97 in 100 not affected)
- Authors' conclusion
Adults with suspected food allergy should receive confirmatory testing so that foods are not avoided unnecessarily.
6. Strengths
- Large, nationally representative
7. Weaknesses
- Self-report, not challenge-confirmed
- Low response rates
8. Risk of bias
- Orienting tool
- none applicable
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Survey methodology.
9. Assessment of the statistical interpretation
10. Relevance to the specific claim
C-FSH-15: shellfish is the most common adult food allergy but affects about 3% of adults, not most people.
11. Independent contrary findings
12. Transferability to Germany and Europe
Moderate.
13. Overall methodological judgement
Confirms minority prevalence.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | high |
| Directness | direct |
| Reproducibility | replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | moderate |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
15. Linked fact checks
- Shrimp, squid and crustaceans are forbidden because they are allergens for most people, are unsuitable for human consumption and are highly antigenic (provoke the immune system). – Studies contradicting or limiting the claim