21 اکتبر 2025, مقالات ISI
Effects of Walnut Consumption on Biomarkers of Oxidative Stress: A Systematic Review and Meta-Analysis
Abstract
Background and Aim
Oxidative stress results from an imbalance between reactive oxygen species production and antioxidant defense mechanisms, contributing to various chronic diseases. Walnuts (Juglans regia L.), rich in polyphenolic compounds, may help reduce oxidative stress. This study systematically reviewed and quantitatively analyzed randomized controlled trials (RCTs) to evaluate the effects of walnut consumption on biomarkers of oxidative stress.
Methods
PubMed, Scopus, Embase, and Web of Science databases were searched up to November 30, 2024. Eligible RCTs assessing walnut intake and oxidative stress biomarkers were included. A random-effects meta-analysis was conducted to estimate pooled weighted mean differences (WMD) and 95% confidence intervals (CIs).
Results
Four RCTs were included. Pooled analysis indicated that walnut consumption significantly increased catalase (CAT) activity (WMD: 42.20; 95% CI: 34.28, 50.11; p < 0.001). However, no significant effects were observed on reduced glutathione (GSH), oxidized glutathione (GSSG), lipid peroxidation (LPO), or oxygen radical absorbance capacity (ORAC).
Conclusion
Walnut consumption enhances catalase activity but does not significantly alter other oxidative stress biomarkers. While walnuts may exert mild antioxidant effects, further high-quality, large-scale trials are warranted to confirm these findings.
Keywords
Walnut; Oxidative stress; Catalase; Antioxidant biomarkers; Meta-analysis; Systematic review.