Randomised controlled trialindependent cross-checkabstract checked★ key study I-EGG-119 in-depth review
Two eggs a day did not worsen blood sugar in people with diabetes
Effect of a high-egg diet on cardiometabolic risk factors in people with type 2 diabetes: the Diabetes and Egg (DIABEGG) Study-randomized weight-loss and follow-up phase.
Overview
Fuller NR et al.. Am J Clin Nutr 2018 · PMID 29741558 · DOI 10.1093/ajcn/nqy048
Over 12 months, a high-egg diet had no adverse effect on glucose, HbA1c or lipids compared with a low-egg diet.
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?
Test a high-egg diet in diabetes.
- How was the study done?
Randomized trial.
- How many people, animals or samples were studied?
128 adults.
- What was actually found?
No differences in glycaemia or lipids.
- How large was the observed effect?
Weight loss equal (-3.1 kg each).
- What do the results mean in everyday life?
Eggs as part of a healthy diet did not harm blood-sugar control.
- What are the study's limitations?
Small; marker outcomes.
- What does it say about Elawady's specific claim?
Argues against eggs causing diabetes through glucose effects.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
It cannot measure new diabetes cases.
Scientific in-depth review
1. Full reference
- Authors
- Fuller NR et al.
- Journal
- Am J Clin Nutr
- Year
- 2018
- Identifier
- PMID 29741558 DOI 10.1093/ajcn/nqy048
- Verification
- verified – PubMed efetch 2026-10-26; Crossref works API 2026-10-26
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
PubMed lists non-US government research support; funding details and any industry support were not verified (abstract only).
2. Research question
Does a high-egg diet (>=12 eggs/week) adversely affect cardiometabolic markers in prediabetes or T2D?
3. Study design and population
- Study design
- Randomised controlled trial – Randomized controlled trial (3-month weight-loss phase plus 6-month follow-up; total 12 months)
- Population
Adults with prediabetes or type 2 diabetes
- Country
Australia
- Period
not stated in abstract
- Sample size
128
- Inclusion and exclusion criteria
not detailed in abstract
4. Methods and endpoints
- Exposure / intervention
>=12 eggs/week
- Comparator
<2 eggs/week
- Endpoints
Weight, glycaemia (glucose, HbA1c, 1,5-anhydroglucitol), lipids, inflammation, oxidative stress
- Statistical methods
Between-group comparisons
5. Actual results
- Results
Weight loss 3-12 months: -3.1 +/- 6.3 vs -3.1 +/- 5.2 kg (P = 0.48). No between-group differences in glycaemia, lipids, inflammation, oxidative stress or adiponectin from 3 to 12 or 0 to 12 months.
- Absolute risks
not reported
- Authors' conclusion
People with prediabetes or T2D on a high-egg weight-loss diet showed no adverse changes in cardiometabolic markers.
6. Strengths
- Randomized, 12 months
- Population at highest suspected risk
7. Weaknesses
- Small; surrogate outcomes
- Background diet emphasised unsaturated fats
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
Dietary trial, not blinded; simplified judgement.
9. Assessment of the statistical interpretation
Null for surrogate markers; cannot address incident diabetes.
10. Relevance to the specific claim
Randomized evidence that eating about two eggs a day within a healthy diet does not worsen glucose control in people with or at risk of T2D.
11. Independent contrary findings
US cohorts (I-EGG-118).
12. Transferability to Germany and Europe
Applicable.
13. Overall methodological judgement
Limits the causal interpretation of the US cohort signal.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | low |
| Directness | indirect |
| Reproducibility | partly replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Long-term incidence trials not available.
15. Linked fact checks
- Higher egg intake is linked to type 2 diabetes. – Studies contradicting or limiting the claim