The Study
Walnut-enriched diet reduces fasting non-HDL-cholesterol and apolipoprotein B in healthy Caucasian subjects: a randomized controlled cross-over clinical trial.
This study shows that eating walnuts was linked to lower 'bad' cholesterol in healthy older white adults. It’s one of the better types of studies because people were randomly assigned to diets, but we don’t know if they knew which diet they were on, so we can’t say for sure that walnuts caused the change.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
This study looked at what happens when older healthy people eat a small handful of walnuts every day for 8 weeks.
Where does this study sit?
Systematic Reviews & Meta-analyses
Max 100Randomized Trials
Max 90Cohort Studies
Max 72Case-Control
Max 58Cross-Sectional
Max 44Case Reports & Series
Max 30Expert Opinion
Max 561 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. Considered the gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1The changes in non-HDL and apoB suggest walnuts may help lower heart disease risk, even if other health markers didn’t change.
- 2Eating 43g of walnuts daily for 8 weeks lowered bad cholesterol (non-HDL) by 10 mg/dL and a heart risk protein (apoB) by 5 mg/dL.
- 3Good cholesterol, blood sugar, and other markers stayed the same.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Metabolism: clinical and experimental
Year
2014
Authors
Liya Wu, K. Piotrowski, Tiina Rau, E. Waldmann, U. Broedl, H. Demmelmair, B. Koletzko, R. Stark, J. Nagel, C. Mantzoros, K. Parhofer
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.