The effect of acute consumption of resistant starch on appetite in healthy adults; a systematic review and meta-analysis of the controlled clinical trials

Background & aims: Although several clinical trials have assessed the effect of Resistant Starch (RS) supplementation on appetite, the results have been inconsistent. Therefore, this study aimed to assess the effect of RS on the healthy adults' rating of appetite. Materials and methods: To this end, Pubmed, CENTRAL, Web of science, Scopus, Medline, and Proquest were systematically searched to find the relevant randomized, and placebo-controlled human trials up to June 2019. As a result, the area under curve (AUC) and standard deviations of the participants' rating appetite were extracted from four eligible studies. Results: Meta-analysis showed a lower appetite in RS group compared to the controls (weighted mean difference [WMD] =-1.375 mm min, 95% confidence interval [95%CI]:-1.673,-1.076). Since high heterogeneity was observed among the included studies (I-2 = 94.5%, P 0.001), subgroup analysis was carried out by RS dose, RS type, duration of supplementation, and time of AUC measuring. In studies that used RS dose of 25 gr, heterogeneity disappeared (P = 0.560, I-2 = 0%). In such studies, a significant reduction was observed in rating of appetite (WMD =-4.513 mm min, 95%CI:-5.270,-3.755; P < 0.001) than studies with RS dose of <25 gr (WMD =-0.799 mm min, 95%CI:-1.123,-0.474; P < 0.001). Additionally, subgroup analysis based on the type of RS showed a significant decrease of appetite in studies that used RS2 (WMD =-4.808 mm min, 95%CI:-5.834,-3.782; P < 0.001) than RS1 (WMD =-0.128 mm min, 95%CI:-0.457, 0.202; P = 0.448). Conclusions: To decrease the rate of appetite more effectively, we suggest other researchers to identify RS dose and type. (C) 2020 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.