Effects of Walnut (Juglans regia L.) on Blood Pressure and Endothelial Function in Adults: A Systematic Review and Dose-Response Meta-Analysis
Mashayekhi G, Ashtary-Larky D, Karimi M, Asbaghi O, Porkar Rezaeyeh A, Shouhani Z, Hosseini A, Naderian M
Journal of human nutrition and dietetics : the official journal of the British Dietetic Association · 0 citations
Review labels
Neutral facts our review recorded about how this study was done. They describe method, never whether we like the result.
How it was studied
- Design
- Meta-analysis (indexed by PubMed)
- Studied in
- People
- Main outcome
- Health markers and function
- Intake measured by
- Not stated
Who paid for it
- Funding
- Funding not disclosed
Publication
- Published
- 2026-08-01 · J Hum Nutr Diet · vol. 39 · issue 4 · p. e70335
- Publisher
- Wiley
- Cited
- 0 citations · more than 67% of similar papers · 0.0× the field average
- References
- 64 works
- Access
- Open access (repository copy)
- Research areas
- Nuts composition and effects · Sirtuins and Resveratrol in Medicine · Peanut Plant Research Studies
- Keywords
- Juglans, Blood pressure, Confidence interval, Randomized controlled trial, Subgroup analysis, Meta-analysis
- MeSH
- endothelium, vascular, humans, juglans, nuts, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, blood pressure, adult, female, male, randomized controlled trials as topic
8 authors
From IR, UA
- Ghazal MashayekhiKerman University of Medical Sciences
- Damoon Ashtary‐LarkyAhvaz Jundishapur University of Medical Sciences
- Mehdi Karimi · correspondingBogomolets National Medical University
- Omid AsbaghiShahid Beheshti University of Medical Sciences
- Arvin Porkar rezaeyehIran University of Medical Sciences
- Zahra ShouhaniAhvaz Jundishapur University of Medical Sciences
Abstract
Background
Walnuts (Juglans regia L.) are rich in bioactive compounds with anti-inflammatory and antioxidant properties, which may benefit cardiovascular health. However, the evidence regarding their effects on blood pressure (BP) and endothelial function remains inconclusive.
Objective
This systematic review and meta-analysis aimed to evaluate the effects of walnut consumption on systolic and diastolic BP (SBP and DBP), and endothelial function markers, including flow-mediated dilation (FMD), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in adults.
Methods
A systematic search of PubMed, Web of Science and Scopus was conducted through February 2026 to identify relevant randomized controlled trials (RCTs). Weighted mean differences (WMDs) with corresponding 95% confidence intervals (CIs) were estimated using a random-effects model. Subgroup analyses were conducted based on intervention duration and walnut dosage. Dose-response associations were further examined using both linear and nonlinear modelling approaches.
Results
Pooled analysis data from 36 RCTs showed no significant overall effect of walnut consumption on SBP (WMD: -0.65 mmHg; 95% CI: -1.61 to 0.30, p = 0.183) or DBP (WMD: -0.68 mmHg; 95% CI: -1.56 to 0.19, p = 0.125). However, significant reductions in DBP were observed in studies lasting ≥ 12 weeks. Walnut intake significantly increased FMD (WMD: 0.93%; 95% CI: 0.27 to 1.59, p = 0.006), but had no overall significant effect on ICAM-1 (WMD = -0.56 ng/mL; 95% CI: -2.50 to 1.38; p = 0.571) and VCAM-1 (WMD: -8.68 ng/mL, p = 0.663). Subgroup analysis indicated a reduction in ICAM-1 in participants at high cardiovascular risk. The dose-response analysis supported a greater effect on ICAM-1 at higher walnut intakes.
Conclusion
Walnut supplementation may improve vascular health by reducing endothelial dysfunction and promoting a dose-dependent reduction in endothelial inflammation.
Trial registration
International Prospective Register of Systematic Reviews (PROSPERO): CRD420261461684.
Abstract via Europe PMC. Copyright remains with the authors or publisher.
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