Effects of green tea supplementation on antioxidant status and inflammatory markers in adults: a grade-assessed systematic review and dose-response meta-analysis of randomised controlled trials

source extracted confidence: high 2026-04-09
#humans #tea #antioxidants #biomarkers #randomized-controlled-trials-as-topic

Effects of green tea supplementation on antioxidant status and inflammatory markers in adults: a grade-assessed systematic review and dose-response meta-analysis of randomised controlled trials

Dehzad et al., 2025 | J Nutr Sci | Meta Analysis

Citation

Dehzad Mohammad Jafar, Ghalandari Hamid, ... Askarpour Moein. Effects of green tea supplementation on antioxidant status and inflammatory markers in adults: a grade-assessed systematic review and dose-response meta-analysis of randomised controlled trials. J Nutr Sci. 2025;14:e25. doi:10.1017/jns.2025.13

Abstract

Green tea, a plant rich in bioactive compounds, has been highlighted for its beneficial effects. In the present systematic review and meta-analysis of randomised controlled trials (RCTs), the impact of green tea on inflammatory and oxidative markers is investigated. Using pre-defined keywords, online databases (PubMed, Scopus, Web of Science Core Collection, and Google Scholar) were searched for relevant articles, published from inception up to February 2024. The outcomes included C-reactive protein (CRP), tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1 beta (IL-1β), total antioxidant capacity (TAC), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPX). Analyses of subgroups, linear, and non-linear associations were also carried out. Out of 1264 records initially retrieved, 38 RCTs were included. Supplementation with green tea improved the following indicators: IL-1β (weighted mean difference (WMD): -0.10 pg/mL; 95% CI: -0.15, -0.06), MDA (WMD: -0.40 mcmol/L; 95 % CI: -0.63, -0.18), TAC (WMD: 0.09 mmol/L; 95% CI: 0.05, 0.13), SOD (WMD: 17.21 u/L; 95% CI: 3.24, 31.19), and GPX (WMD: 3.90 u/L; 95% CI: 1.85, 5.95); but failed to improve others, including CRP (WMD: 0.01 mg/L; 95% CI: -0.14, 0.15), IL-6 (WMD: -0.34 pg/mL; 95% CI:-0.94, 0.26), and TNF-α (WMD: -0.07 pg/mL; 95% CI: -0.42, 0.28). Supplementation with green tea can improve the body's oxidative status. However, the results showed no significant effect of green tea on inflammatory markers, except for IL-1β. Further studies are needed to determine the effectiveness of green tea, particularly on inflammatory status.

Key Findings

Further studies are needed to determine the effectiveness of green tea, particularly on inflammatory status.

Outcomes Measured

  • C-reactive protein
  • inflammatory markers

Population

Field Value
Population See abstract
Sample Size 38
Age Range See abstract
Condition See abstract

MeSH Terms

  • Humans
  • Tea
  • Antioxidants
  • Biomarkers
  • Randomized Controlled Trials as Topic
  • Dietary Supplements
  • Inflammation
  • Adult
  • C-Reactive Protein
  • Oxidative Stress
  • Male
  • Female

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Systematic Review, Meta-Analysis
  • Vertical: green-tea

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09