Effects of non-soy legume consumption on C-reactive protein: A systematic review and meta-analysis

Abstract

Objectives: Because of conflicting results of presented studies, the aim of this systematic review and meta-analysis of randomized clinical trials (RCTs) was to examine the effect of non-soy legume intake on inflammatory markers and C-reactive protein (CRP). Methods: We searched Pubmed, ISI Web of Knowledge, SCOPUS, and Google Scholar for relevant studies up to July 2013, using medical subject headings MeSH and other related keywords. Nine RCTs were systematically reviewed to examine the effect of non-soy legume consumption on inflammatory markers. Eight studies involving 464 participants were included in the meta-analysis. Results: The results of the meta-analysis showed that non-soy legume consumption had a trend toward a significant effect on decreasing CRP and high-sensitivity (hs)-CRP concentrations (mean difference (MD) = -0.21; 95% confidence interval CI, -0.44 to 0.02; P = 0.068). There was no overall effect of non-soy legume consumption on CRP or hs-CRP levels in either the parallel or crossover study designs. Our subgroup analysis of CRP type and study design, showed that non-soy legume intake had a significant effect on CRP levels in parallel studies (MD = -1.01; 95% CI, -1.78 to -0.23; P = 0.011) and a significant effect on hs-CRP levels (MD = -0.53; 95% CI, -0.95 to -0.11; P = 0.014) and in the crossover sub group (MD = -0.68; 95% Cl, -1.28 to -0.08; P = 0.026). Conclusions: This review of RCTs showed that non-soy legume consumption may contribute to reductions in CRP and hs-CRP concentrations. However, further controlled clinical trials are needed to investigate the effect of non-soy legume intake on other inflammatory markers. (C) 2015 Elsevier Inc. All rights reserved.