EFFECTS OF FLAXSEED SUPPLEMENTS ON INFLAMMATORY BIOMARKERS: A SYSTEMATIC REVIEW AND META-ANALYSIS OF CONTROLLED CLINICAL TRIAL

Background and Aim: Many experimental and clinical trials suggested that flaxseed might be a potent anti-inflammatory agent, but the evidences concerning the effects of flaxseed supplements on inflammation has not been fully conclusive. We aimed to assess the impact of the effects of flaxseed supplements on inflammatory biomarkers through systematic review of literature and meta-analysis of available randomized controlled trials (RCTs).Methods: The literature search included PUBMED, Cochrane Library, Scopus, and EMBASE up to February 2015 to identify RCTs investigating the effect of flaxseed supplements on plasma blood pressure. Effect size was expressed as weighed mean difference (WMD) and 95% confidence interval (CI).Results: 31 trials with 1502, which included 936 in intervention group and 566 in control group were included in this meta-analysis. Random-effects meta-analysis suggested significant reductions in CRP (WMD=-0.56 [95% CI: -1.03, -0.10], p = 0.02), hs-CRP (mean difference=-0.69 [95% CI: -1.22, -0.16], P=0.01), and TNF- (WMD=-0.38 [95% CI: -0.75, 0.01]; P =0.07 ) following supplementation with flaxseed products. We could not found any significant reduction in IL-6 concentration after flaxseed intake IL-6 (WMD=-0.25 [95% CI: -0.70, 0.21]; P =0.28). However, sensitivity analysis for IL-6 suggests a significant change in the results following the exclusion one of the study. For all biomarkers, heterogeneity between studies was high and when the studies were stratified according to their duration, supplement dose and study quality, source of the heterogeneity identified. Conclusion: Our results showed that flaxseed or its derivatives can have anti-inflammatory effects in the human body

Keywords:

flaxseed , inflammation , inseed , meta-analysis , systematic review