Effects of resistant dextrin on glycemic traits: a systematic review and meta-analysis of randomized controlled trials

Chronic hyperglycemia has affected billions of people currently and has emerged as an alarming public health concern for decades. Resistant dextrin (RD), an indigestible glucan with various applications in the food industry, has been reported to improve insulin sensitivity and help blood glucose control. However, the effect of RD on glucose metabolism was not systematically and comprehensively reviewed. The present study aimed to investigate the effect of RD on glycemic markers, including fasting blood glucose (FBG), fasting blood insulin (FBI), glycated hemoglobin (HbA1c), and homeostasis model assessment of insulin resistance (HOMA-IR). PubMed, Embase, Web of Science, Scopus, Cochrane library databases, and other additional records were systematically retrieved for randomized controlled trials (RCTs) on the effect of resistant dextrin intervention on FBG, FBI, HbA1c, HOMA-IR up to October 2024. Data were pooled using weighted mean difference (WMD) and 95% confidence intervals (95%CI), with P value ≤ 0.05 as statistical significance. Risk of bias was assessed with the Cochrane tool. Certainty of evidence was assessed with Grading of Recommendations Assessment, Development and Evaluation approach. A total of 13 RCTs were eligible. RD significantly reduced FBG (WMD: -0.15 mmol/L, 95%CI: -0.30 to -0.00 mmol/L; P = 0.049; I2 = 77.5%; 13 trials; 952 participants) and HOMA-IR (WMD: -0.51; 95% CI: -0.93 to -0.09; P = 0.02; I2 = 25.2%; 7 trials;332 participants), while modestly improved HbA1c (WMD: -0.18%; 95%CI: -0.39 to 0.02%; P = 0.07; I2 = 62.0%; 10 trials; 788 participants). The effect of RD on FBI was not significant (WMD: -4.26 pmol/L; 95%CI: -13.05 to 4.53 pmol/L; P = 0.29; I2 = 65.0%; 8 trials; 625 participants). Subgroup analysis revealed that RD was more beneficial to overweight/obese or diabetic patients than the non-obese and non-diabetic. A dosage of 10 g per day was the most frequently used dose that showed efficacy. This study is so far the most extensive systematic review to evaluate the role of RD on markers of glycemic control. RD interventions can exert beneficial effects on FBG and HOMA-IR. Further high-quality and long-term studies are needed to strengthen its credibility. This systematic review was registered on PROSPERO (international prospective register of systematic reviews) as CRD42023429881.