Cohort studyindependent cross-checkabstract checked★ key study I-FRU-106 in-depth review
Fresh fruit and diabetes in half a million Chinese adults
Fresh fruit consumption in relation to incident diabetes and diabetic vascular complications: A 7-y prospective study of 0.5 million Chinese adults.
Overview
Du H et al.. PLoS Med 2017 · PMID 28399126 · DOI 10.1371/journal.pmed.1002279
Daily fruit eaters had a 12% lower diabetes risk, and people with diabetes who ate more fruit had fewer deaths and complications.
Does the study support the specific claim? Yes · Methodological quality: high
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Study fruit and diabetes outcomes.
- How was the study done?
Large cohort.
- How many people, animals or samples were studied?
~0.5 million adults.
- What was actually found?
Lower risks with more fruit.
- How large was the observed effect?
HR 0.88; mortality HR 0.83 per 100 g/d.
- What do the results mean in everyday life?
Whole fruit fits a diet for people with or at risk of diabetes.
- What are the study's limitations?
Observational.
- What does it say about Elawady's specific claim?
Supports C-FRU-05.
- Do the results apply to Germany and Europe?
Plausible.
- What can explicitly not be concluded from this study?
It cannot prove that fruit causes the lower risk.
Scientific in-depth review
1. Full reference
- Authors
- Du H et al.
- Journal
- PLoS Med
- Year
- 2017
- Identifier
- PMID 28399126 DOI 10.1371/journal.pmed.1002279 · PMC5388466
- Verification
- verified – PubMed efetch 2026-10-26 + Crossref works API
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
Medical Research Council, Cancer Research UK and other grants (PubMed grant list); one author on the PLOS Medicine editorial board.
2. Research question
Is fresh fruit consumption associated with incident diabetes and, among people with diabetes, with death and vascular complications?
3. Study design and population
- Study design
- Cohort study – Prospective cohort (China Kadoorie Biobank)
- Population
0.5 million adults aged 30-79 in 10 regions of China
- Country
China
- Period
Recruitment 2004-2008; ~7 years follow-up
- Sample size
482,591 without diabetes; 30,300 with diabetes
- Inclusion and exclusion criteria
CKB participants.
4. Methods and endpoints
- Exposure / intervention
Self-reported fresh fruit frequency/amount
- Comparator
Never/rarely
- Endpoints
Incident diabetes; mortality; macro- and microvascular disease
- Statistical methods
Cox regression adjusted for age, sex, region, SES, lifestyle, BMI, family history
5. Actual results
- Results
Incident diabetes HR 0.88 (0.83-0.93) daily vs non-consumers (0.2% difference in 5-y absolute risk). In diabetes: all-cause mortality HR 0.83 (0.74-0.93) per 100 g/d; microvascular 0.72 (0.61-0.87); macrovascular 0.87 (0.82-0.93); 5-y absolute risk differences 1.9%, 1.1% and 5.4% (daily vs non-consumers).
- Absolute risks
Reported: 0.2% (incident diabetes); 1.9%, 1.1%, 5.4% in people with diabetes.
- Authors' conclusion
Higher fresh fruit consumption was associated with lower diabetes risk and, among diabetic individuals, lower risks of death and complications.
6. Strengths
- Very large
- Includes people with diabetes
- Absolute risks reported
7. Weaknesses
- Observational; residual confounding (authors' stated limitation)
- Reverse causation possible (diagnosed patients avoided fruit)
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
Confounding by socioeconomic status; reverse causation.
9. Assessment of the statistical interpretation
CIs log-symmetric; absolute differences small for incident diabetes (stats/C-FRU-05_du2017_christensen.py).
10. Relevance to the specific claim
Supports that sweet whole fruits need not be avoided, including by people with diabetes (C-FRU-05); contradicts the general fruit-glycaemic fear behind C-FRU-01.
11. Independent contrary findings
I-FRU-109 (positive association in Korean women).
12. Transferability to Germany and Europe
Plausible.
13. Overall methodological judgement
Strong observational support for whole fruit.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | high |
| Risk of bias | some concerns |
| Precision of results | high |
| 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
Fruit types.
15. Linked fact checks
- Sweet fruits such as dates, grapes, figs and mango need not be avoided; conventional diets wrongly restrict them and push bland fruit. – Studies supporting the claim
- Watermelon and melon (cantaloupe) should be avoided; the archive's food page supports this with studies showing that a high dietary glycaemic load raises type 2 diabetes risk. – Studies contradicting or limiting the claim