Randomised controlled trialindependent cross-checkabstract checked★ key study I-SOD-118 in-depth review
Sugar drinks made children gain more weight
A trial of sugar-free or sugar-sweetened beverages and body weight in children.
Overview
de Ruyter JC et al.. N Engl J Med 2012 · PMID 22998340 · DOI 10.1056/NEJMoa1203034
In an 18-month blinded trial, Dutch children given one sugary drink a day gained about 1 kg more than children given an identical-tasting sugar-free drink.
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?
Test whether replacing sugary drinks with sugar-free drinks reduces weight gain in children.
- How was the study done?
Children received one can a day of either drink for 18 months without knowing which.
- How many people, animals or samples were studied?
641 Dutch school children.
- What was actually found?
Less weight and fat gain with sugar-free drinks.
- How large was the observed effect?
Weight difference about -1.0 kg; BMI z -0.13.
- What do the results mean in everyday life?
Liquid sugar adds weight because children do not eat less to compensate.
- What are the study's limitations?
Many children stopped drinking; sensitivity analysis borderline.
- What does it say about Elawady's specific claim?
Supports the claim.
- Do the results apply to Germany and Europe?
Directly European.
- What can explicitly not be concluded from this study?
Cannot speak to adults or long-term disease.
Scientific in-depth review
1. Full reference
- Authors
- de Ruyter JC et al.
- Journal
- N Engl J Med
- Year
- 2012
- Identifier
- PMID 22998340 DOI 10.1056/NEJMoa1203034
- Verification
- verified – PubMed efetch 2026-10-26 + Crossref 2026-10-26
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
Netherlands Organization for Health Research and Development and others (PubMed abstract)
2. Research question
Does masked replacement of sugar-containing beverages with non-caloric beverages reduce weight gain in children?
3. Study design and population
- Study design
- Randomised controlled trial – Double-blind randomised controlled trial, 18 months (DRINK; NCT00893529)
- Population
Primarily normal-weight children aged 4 years 10 months to 11 years 11 months
- Country
Netherlands
- Period
18 months
- Sample size
641 (477 completed)
- Inclusion and exclusion criteria
School children; details in full text
4. Methods and endpoints
- Exposure / intervention
250 mL/day sugar-containing beverage (104 kcal)
- Comparator
250 mL/day artificially sweetened, sugar-free beverage
- Endpoints
BMI z score; weight; skinfolds; waist-to-height ratio; fat mass
- Statistical methods
Intention-to-treat with imputation
5. Actual results
- Results
BMI z score +0.02 (sugar-free) vs +0.15 (sugar); difference CI -0.21 to -0.05. Weight +6.35 vs +7.37 kg (difference CI -1.54 to -0.48). Skinfolds, waist-to-height ratio and fat mass increased less in the sugar-free group. 26% stopped drinking the beverages; among completers plus measured dropouts, BMI z +0.06 vs +0.12 (P=0.06).
- Absolute risks
not applicable
- Authors' conclusion
Masked replacement of sugar-containing beverages with non-caloric beverages reduced weight gain and fat accumulation in normal-weight children.
6. Strengths
- Double-blind (masked drinks)
- 18 months
- Objective measures
7. Weaknesses
- 26% discontinued
- Sensitivity analysis borderline (P=0.06)
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
Missing data handled by imputation.
9. Assessment of the statistical interpretation
Recalculated differences (-0.13 BMI z; -1.02 kg) match reported CIs (stats/C-SOD-02_deruyter.py). Blinding makes incomplete compensation for liquid sugar the most likely explanation.
10. Relevance to the specific claim
Strongest randomised evidence for C-SOD-02: sugary drinks cause extra weight gain in children, and because drinks were masked, children did not fully compensate for the liquid sugar calories.
11. Independent contrary findings
Ebbeling 2012 (I-SOD-119) found no difference at 2 years in adolescents.
12. Transferability to Germany and Europe
European trial; directly applicable.
13. Overall methodological judgement
High-quality causal evidence that sugar-sweetened drinks increase weight gain in children.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | high |
| Risk of bias | some concerns |
| Precision of results | moderate |
| Directness | direct |
| Reproducibility | replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Long-term persistence.