Kolahi Ahmadreza, Movahed Samira, Tejareh Faezeh, Saeedy Said Abdul Ghafour, Gholizadeh Mohammad
Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
Department of Nutrition, Electronic Health and Statistics Surveillance Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Sci Rep. 2025 Aug 13;15(1):29632. doi: 10.1038/s41598-025-14701-w.
Oxidative stress, an imbalance between reactive oxygen species and antioxidants, contributes to chronic diseases. Almonds, rich in vitamin E, polyphenols, and monounsaturated fats, exhibit antioxidant potential, though their overall effects on oxidative biomarkers are unclear. This systematic review and meta-analysis evaluate almond supplementation's impact on these biomarkers in adults. Following PRISMA guidelines, PubMed, Scopus, and Web of Science were searched up to January 2025. Randomised controlled trials (RCTs) and crossover trials assessing biomarkers of antioxidant and oxidation status (e.g., malondialdehyde [MDA], superoxide dismutase [SOD], glutathione peroxidase [GPx], 8-hydroxy-2'-deoxyguanosine [8-OHdG], uric acid [UA]) were included. Risk of bias was evaluated using the Cochrane Tool, and random-effects models calculated weighted mean differences (WMDs) with 95% confidence intervals (CIs). Eight studies (5 RCTs, 3 crossover trials; n = 424) were included. Almond doses of > 60 g/day significantly reduced MDA (WMD = -0.46, p = 0.002), 8-OHdG (WMD = -5.83, p < 0.001), and UA (WMD = -0.64, p = 0.009), while increasing SOD (WMD = 2.02, p = 0.008). No effect was found for GPx (p = 0.270). High heterogeneity (I² = 92-96%) indicated variability in study design, dosage, and population. Almond supplementation (> 60 g/day) significantly improves oxidation status by reducing MDA, 8-OHdG, and UA while enhancing SOD activity. These findings support almonds as a functional food for oxidation management. However, high heterogeneity underscores the need for standardized trials to confirm optimal dosage, duration, and conditions. Trial registration: Prospero-CRD42025646264.
氧化应激是活性氧与抗氧化剂之间的失衡状态，它会引发慢性疾病。杏仁富含维生素E、多酚和单不饱和脂肪，具有抗氧化潜力，但其对氧化生物标志物的总体影响尚不清楚。本系统评价和荟萃分析评估了杏仁补充剂对成年人这些生物标志物的影响。按照PRISMA指南，检索了截至2025年1月的PubMed、Scopus和Web of Science数据库。纳入了评估抗氧化和氧化状态生物标志物（如丙二醛[MDA]、超氧化物歧化酶[SOD]、谷胱甘肽过氧化物酶[GPx]、8-羟基-2'-脱氧鸟苷[8-OHdG]、尿酸[UA]）的随机对照试验（RCT）和交叉试验。使用Cochrane工具评估偏倚风险，并采用随机效应模型计算加权平均差（WMD）及95%置信区间（CI）。共纳入8项研究（5项RCT、3项交叉试验；n = 424）。每日杏仁摄入量> 60克可显著降低MDA（WMD = -0.46，p = 0.002）、8-OHdG（WMD = -5.83，p < 0.001）和UA（WMD = -0.64，p = 0.009），同时提高SOD（WMD = 2.02，p = 0.008）。未发现对GPx有影响（p = 0.270）。高度异质性（I² = 92 - 96%）表明研究设计、剂量和人群存在差异。补充杏仁（> 60克/天）可通过降低MDA、8-OHdG和UA并增强SOD活性，显著改善氧化状态。这些发现支持杏仁作为一种用于氧化管理的功能性食品。然而，高度异质性凸显了进行标准化试验以确定最佳剂量、持续时间和条件的必要性。试验注册号：Prospero - CRD42025646264。
