Randomised controlled trialindependent cross-checkabstract checked★ key study I-FRU-105 in-depth review
Should people with type 2 diabetes cut down on fruit?
Effect of fruit restriction on glycemic control in patients with type 2 diabetes--a randomized trial.
Overview
Christensen AS et al.. Nutr J 2013 · PMID 23497350 · DOI 10.1186/1475-2891-12-29
Telling newly diagnosed patients to eat less fruit did not improve their blood sugar, weight or waist.
Does the study support the specific claim? Yes · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Test fruit restriction advice.
- How was the study done?
RCT, 12 weeks.
- How many people, animals or samples were studied?
63 adults with new T2D.
- What was actually found?
No HbA1c difference.
- How large was the observed effect?
0.19% (-0.23 to 0.62).
- What do the results mean in everyday life?
Whole fruit can stay in the diet of people with type 2 diabetes.
- What are the study's limitations?
Small, short, open.
- What does it say about Elawady's specific claim?
Supports C-FRU-05.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
It does not cover juices or insulin users.
Scientific in-depth review
1. Full reference
- Authors
- Christensen AS et al.
- Journal
- Nutr J
- Year
- 2013
- Identifier
- PMID 23497350 DOI 10.1186/1475-2891-12-29 · PMC3599615
- Verification
- verified – PubMed efetch 2026-10-26 + Crossref works API
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
Not stated in abstract.
2. Research question
Does advice to restrict fruit change HbA1c in newly diagnosed type 2 diabetes?
3. Study design and population
- Study design
- Randomised controlled trial – Open randomised controlled trial, two parallel groups, 12 weeks
- Population
63 overweight adults with newly diagnosed T2D
- Country
Not stated in abstract (trial NCT01010594)
- Period
12 weeks
- Sample size
63
- Inclusion and exclusion criteria
Newly diagnosed T2D.
4. Methods and endpoints
- Exposure / intervention
Medical nutrition therapy + advice to eat >=2 pieces of fruit/day
- Comparator
Medical nutrition therapy + advice to eat <=2 pieces/day
- Endpoints
HbA1c; weight; waist; fruit intake
- Statistical methods
Intention to treat
5. Actual results
- Results
High-fruit group +125 g/day fruit (95% CI 78-172); low-fruit group -51 g. HbA1c fell in both groups with no difference (0.19%, -0.23 to 0.62); no difference in weight or waist loss. All patients completed.
- Absolute risks
Not applicable
- Authors' conclusion
Fruit intake should not be restricted in patients with type 2 diabetes.
6. Strengths
- Randomised, ITT, no dropouts
- Direct question
7. Weaknesses
- Small; 12 weeks
- Open-label; self-reported intake
- Newly diagnosed patients only
8. Risk of bias
- Orienting tool
- RoB 2
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Open design; self-reported intake.
9. Assessment of the statistical interpretation
CI consistent with the point estimate; upper limit 0.62% leaves imprecision (stats/C-FRU-05_du2017_christensen.py).
10. Relevance to the specific claim
Directly supports the point that whole fruit need not be restricted in T2D (C-FRU-05).
11. Independent contrary findings
Not applicable to juices or dried fruit in large amounts.
12. Transferability to Germany and Europe
Directly applicable.
13. Overall methodological judgement
Small but direct RCT support for not restricting whole fruit.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | low |
| Directness | direct |
| Reproducibility | partly replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Insulin-treated patients; dates and dried fruit.