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Favism at different ages
Favism: Clinical Features at Different Ages.
Overview
Beretta A et al.. Nutrients 2023 · PMID 36678214 · DOI 10.3390/nu15020343
Fava beans trigger haemolysis through vicine and convicine, which other legumes do not contain; infants and young children are most at risk.
Does the study support the specific claim? Partly · Methodological quality: low
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Describe favism by age.
- How was the study done?
Narrative review of case reports.
- How many people, animals or samples were studied?
Published cases worldwide.
- What was actually found?
Severity highest in infants; raw beans most risky.
- How large was the observed effect?
Only ~25% of deficient adults react.
- What do the results mean in everyday life?
People with G6PD deficiency should avoid fava beans; other legumes are not known triggers.
- What are the study's limitations?
Case-based, no systematic search.
- What does it say about Elawady's specific claim?
Limits the lentil claim and the universal ban.
- Do the results apply to Germany and Europe?
Universal biology.
- What can explicitly not be concluded from this study?
It cannot rule out rare reactions to other pulses.
Scientific in-depth review
1. Full reference
- Authors
- Beretta A et al.
- Journal
- Nutrients
- Year
- 2023
- Identifier
- PMID 36678214 DOI 10.3390/nu15020343 · PMC9864644
- Verification
- verified – PubMed efetch 2026-10-26 + Crossref works API
- Retracted
- no
- Corrections
- none
- Extent checked
- full text
- Conflicts of interest and funding
Italian Ministry of Health Current Research funding; no conflicts declared.
2. Research question
What are the predisposing factors and clinical features of favism at different ages?
3. Study design and population
- Study design
- Narrative review – Narrative review of case reports and case series of favism by age group
- Population
Published favism cases (pregnant/breastfeeding, children, adolescents, adults)
- Country
International (authors in Italy)
- Period
Literature from the 1950s to the 2020s
- Sample size
Not applicable (case literature)
- Inclusion and exclusion criteria
Case reports/series of favism.
4. Methods and endpoints
- Exposure / intervention
Fava bean ingestion (raw, cooked, frozen, via breast milk)
- Comparator
Not applicable
- Endpoints
Clinical features, severity
- Statistical methods
Descriptive
5. Actual results
- Results
Triggers are vicine and convicine (converted to divicine and isouramil); 'other legumes do not present the triggering agents'. Only about 25% of deficient adults develop a crisis after fava beans; raw beans are more likely to trigger crises than cooked, frozen or canned ones. Deaths were reported in infants (including via maternal fava intake during pregnancy/breastfeeding). The review states that some associations advise avoiding all pulses but that 'no consideration can be made' on this from the reviewed evidence.
- Absolute risks
Not applicable
- Authors' conclusion
Known G6PD-deficient people should eliminate fava beans; effects of other pulses need study; severity is highest in the youngest children and in pregnancy.
6. Strengths
- Full text read
- Covers all age groups, including breastfed infants
7. Weaknesses
- Narrative, case-based; no systematic search reported in detail
- Publication bias towards severe cases
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
Narrative review of case reports.
9. Assessment of the statistical interpretation
No quantitative synthesis; the 25% figure is cited from earlier literature.
10. Relevance to the specific claim
Confirms favism and its severity in children (C-LEG-03); states that other legumes lack the triggering compounds (contradicts lentil part of C-LEG-05); shows that not all deficient people react and non-deficient people are unaffected (limits C-LEG-04).
11. Independent contrary findings
None on the core mechanism.
12. Transferability to Germany and Europe
Universal biology.
13. Overall methodological judgement
Useful clinical overview; supports targeted, not universal, fava avoidance.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | low |
| Risk of bias | some concerns |
| Precision of results | not applicable |
| Directness | direct |
| Reproducibility | partly replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | moderate |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Risk from other pulses in different G6PD variants has not been studied systematically.
15. Linked fact checks
- In G6PD deficiency, haemolysis is triggered by merely smelling fava beans and by eating lentils, as well as by aspirin and antibiotics. – Studies contradicting or limiting the claim
- Because of favism (and the other narrow risks), legumes should be excluded from everyone's diet. – Studies contradicting or limiting the claim