Effects of supplementation with green tea catechins on plasma C-reactive protein concentrations: A systematic review and meta-analysis of randomized controlled trials

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#anti-inflammatory-agents #c-reactive-protein #camellia-sinensis #catechin #dietary-supplements

Effects of supplementation with green tea catechins on plasma C-reactive protein concentrations: A systematic review and meta-analysis of randomized controlled trials

Serban et al., 2015 | Nutrition | Meta Analysis

Citation

Serban Corina, Sahebkar Amirhossein, ... Banach Maciej. Effects of supplementation with green tea catechins on plasma C-reactive protein concentrations: A systematic review and meta-analysis of randomized controlled trials. Nutrition. 2015-Sep;31(9):1061-71. doi:10.1016/j.nut.2015.02.004

Abstract

BACKGROUND: Promising experimental and clinical trials suggest that green tea decreases the inflammatory process in cardiometabolic diseases, but evidence from epidemiologic studies about the effects on plasma C-reactive protein (CRP) seems inconsistent and ambiguous. Therefore, the aim of this meta-analysis was to evaluate the effects of green tea supplementation on plasma CRP concentrations. METHODS: We searched selected database up to October 26, 2014 to identify randomized controlled trials (RCTs) investigating the effects of green tea supplementation on plasma CRP concentrations. Two independent reviewers extracted data on study characteristics, methods, and outcomes. RESULTS: Meta-analysis of data from 11 RCTs arms did not indicate a significant effect of supplementation with green tea catechins on plasma CRP concentrations (weighted mean difference [WMD], 0.085 mg/L; 95% confidence interval [CI], -0.225 to 0.395; P = 0.592). This effect size was robust in sensitivity analysis and omission of each individual study did not have a significant effect. The nonsignificant effects of green tea catechins on plasma CRP concentrations were also observed in subgroups of studies with green tea supplementation with a duration of <8 wk (WMD, 0.029 mg/L; 95% CI, -0.229 to 0.286; P = 0.828) and ≥8 wk (WMD, 0.099 mg/L; 95% CI, -0.555 to 0.754; P = 0.766). Likewise, there was no significant effect in subgroups of studies with total catechins doses <400 mg/d (WMD, 0.073 mg/L; 95% CI, -0.251 to 0.398; P = 0.658) and ≥400 mg/d (WMD, 0.213 mg/L; 95% CI, -0.148 to 0.574; P = 0.247). The effect sizes were not significant after stratification of studies to those recruiting healthy subjects (WMD, -0.028 mg/L; 95% CI, -0.216 to 0.160; P = 0.769), and those recruiting participants with cardiometabolic diseases (WMD, 0.260 mg/L; 95% CI, -0.815 to 1.334; P = 0.636). CONCLUSIONS: This meta-analysis of data from 11 RCT arms did not indicate a significant effect of supplementation with green tea catechins on plasma CRP concentrations. Furthermore, well-designed trials are necessary to validate these results.

Key Findings

Meta-analysis of data from 11 RCTs arms did not indicate a significant effect of supplementation with green tea catechins on plasma CRP concentrations (weighted mean difference [WMD], 0.085 mg/L; 95% confidence interval [CI], -0.225 to 0.395; P = 0.592). This effect size was robust in sensitivity analysis and omission of each individual study did not have a significant effect. The nonsignificant effects of green tea catechins on plasma CRP concentrations were also observed in subgroups of studie

Outcomes Measured

  • C-reactive protein
  • inflammatory markers

Population

Field Value
Population See abstract
Sample Size 11
Age Range See abstract
Condition See abstract

MeSH Terms

  • Anti-Inflammatory Agents
  • C-Reactive Protein
  • Camellia sinensis
  • Catechin
  • Dietary Supplements
  • Humans
  • Inflammation
  • Plant Extracts
  • Tea

Evidence Classification

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

Provenance

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