Effect of quercetin supplementation on serum CRP levels: a systematic review and meta-analysis of randomized controlled trials

  • Masoud Khorshidi Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
  • Sakineh Shab-Bidar 1Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
  • Hamed Kord-Varkaneh Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), Tehran, Iran
  • Kurosh Djafarian Mail 2Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), Tehran, Iran
Quercitin, C-reactive protein, Meta-analysis


Background: Several studies have investigated the effect of quericitn supplementation on serum C - reactive protein (CRP). However, results were inconsistent. This systematic review and meta-analysis was designed to assess the effect of quercetin supplementation on CRP levels in randomize control trials (RCTs).
Method: We searched PubMed and Scopus up to July 2016 to identify RCTs investigating the effect of quercetin on serum CRP. Meta-analysis was performed using either a fixed-effects or random-effect model according to I² statistic. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) were calculated for net changes in CRP levels.
Results: Seven trials with eight data sets and 346 participants met the inclusion criteria. There was no significant differences for CRP reduction between subjects with quercetin supplementation and placebo control [WMD, 0.01 mg/L; 95% CI: -0.18 to 0.21, p =0.88] with significant heterogeneity (I²=48.9%; p=0.05). Subgroup analyses showed that dose, duration and country were not the potential sources of heterogeneity.
Conclusion: Our results suggest that quercetin supplementation does not reduce serum CRP. Further large and well-designed studies are necessary to confirm this conclusion. 


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How to Cite
Khorshidi M, Shab-Bidar S, Kord-Varkaneh H, Djafarian K. Effect of quercetin supplementation on serum CRP levels: a systematic review and meta-analysis of randomized controlled trials. J Nutr Sci & Diet. 2(3).
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