Effects of resistant starch interventions on circulating inflammatory biomarkers: a systematic review and meta-analysis of randomized controlled trials

PURPOSE: This study aimed to summarize earlier studies on the effects of RS consumption on the serum levels of inflammatory biomarkers. METHODS: A comprehensive search was done in the electronic databases that published from 1988 up to May 2019. Two reviewers independently performed screening, data extraction, and risk-of-bias assessment. We used from the effect size, as estimated by the mean difference to perform the fixed method meta-analysis. RESULTS: Overall, 13 studies with 14 effect sizes met the inclusion criteria and were included in the final analysis. Sample size of these studies ranged from 15 to 75 and intervention duration ranged from 4 to 14 weeks. Meta-analysis revealed that higher consumption of resistant starch caused a significant reduction in the interleukin 6 (weighted mean difference = − 1.11 pg/mL; 95% CI: − 1.72, − 0.5 pg/mL; P = < 0.001) and tumor necrosis factor alpha (weighted mean difference = − 2.19 pg/mL; 95% CI: − 3.49, − 0.9 pg/mL; P = 0.001) levels. However, no significant changes were found in C-reactive protein concentration (weighted mean difference = − 0.21 mg/L; 95% CI: − 1.06, 0.63 mg/L; P = 0.61). Moreover, the changes in interleukin 6 concentration was dependent on study quality and intervention duration. CONCLUSION: The current meta-analysis indicated that RS intake can improve some inflammatory biomarkers. More research, with a large sample sizes and accurate design is recommended.