Evidence map›Paper›PMID 40804320›Full record

SynthesisScientific reports2025

The impact of almond supplementation on oxidative stress biomarkers: a systematic review and meta-analysis of randomized control trials.

Ahmadreza Kolahi, Samira Movahed, Faezeh Tejareh, Said Abdul Ghafour Saeedy, Mohammad Gholizadeh

Abstract readSystematic ReviewMeta-Analysis
In one paragraph

Synthesis in Scientific reports, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

4 citing papers in PubMed.

  1. Trial
  2. Trial
  3. Ageing in Unani medicine: Conceptual framework and modulatory approaches.Journal of Ayurveda and integrative medicine · 2026
    Review
  4. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors.

Ahmadreza KolahiDepartment of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
Samira MovahedDepartment of Nutrition, Electronic Health and Statistics Surveillance Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Faezeh TejarehDepartment of Nutrition, Faculty of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
Said Abdul Ghafour SaeedyDepartment of Paraclinic, School of Medicine, Herat University, Herat, Afghanistan.
Mohammad GholizadehDepartment of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran. mgholizadeh@sbmu.ac.ir.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

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.

Indexed as

BiomarkersDietary SupplementsOxidative StressPrunus dulcisAntioxidantsHumansRandomized Controlled Trials as TopicSuperoxide DismutaseAntioxidantsBiomarkersSuperoxide DismutaseAlmondsAntioxidantsBiomarkersMeta-analysisOxidative stress

Identifiers

PMID40804320
PMCPMC12350649

What Socratic holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.