Fermented Foods and Inflammation: A Systematic Review and Meta-Analysis of Randomized Controlled Trials Publisher Pubmed



Saeidifard N¹ ; Djafarian K² ; Shabbidar S¹
Source: Clinical Nutrition ESPEN Published:2020

Abstract

Objective: The effect of fermented foods consumption on inflammation has been investigated in several studies, but findings are inconsistent. Therefore we conducted a meta-analysis to examine the effect of fermented foods on inflammatory biomarkers including C-reactive protein (CRP), interleukin (IL)-6 and tumor necrosis factor (TNF)-α in the general adult population. Design: systematic review and meta-analysis. Methods: In this systematic review and meta-analysis, randomized controlled trials in the general adult population comparing fermented foods with a control product were searched from two literature databases (PubMed and Scopus) up to June 4, 2019. Trials with mean difference (MD) of 95% confidence interval (CI) were pooled using random effect model. Heterogeneity was assessed using Cochran's Q and I2 tests. Subgroup analysis was applied to define possible sources of heterogeneity. Results: The search strategy identified 3293 documents. Overall, 26 publications with 1461 people met the inclusion criteria. Our results indicated that intake of fermented foods could reduce serum TNF-α levels ((WMD = -8.26, 95% CI: −14.61, −1.91, p = 0.01; I2 = 99.9%, p < 0.001)). However, no change was observed in serum levels of CRP ((WMD = −0.21, 95% CI: −0.47, 0.05, p = 0.11), I2 = 93.8%, p < 0.001) and IL-6 ((WMD = 0.31, 95% CI:-3.79, 4.43, p = 0.88), I2 = 99.3%, p < 0.001). Conclusion: Our findings showed that intake of fermented foods did not improve serum CRP and IL-6. We observed a reduction in pooled effect of TNF-α following intake of fermented foods. © 2019 European Society for Clinical Nutrition and Metabolism