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

Background: Several studies have investigated the effect of quericitn supplementation on serum C reactive protein (CRP). However, results were inconsistent. This systematic review and metaanalysis 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. Metaanalysis was performed using either a #xFB01;xedeffects or randomeffect model according to I #xB2; 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 (I #xB2;=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 welldesigned studies are necessary to confirm this conclusion. #xA0;