The Effect of Resistant Starch Bagels on Glycemic Response in Adults at Risk for Type 2 Diabetes

Abstract

Acute and chronic resistant starch (RS) consumption has been shown to improve glycemia, however, more chronic interventions using high-RS foods are needed in individuals at increased risk of type 2 diabetes (T2D). A randomized, double-blind crossover study was conducted to examine the glycemic effects of 8-week consumption of high-RS bagels (25 g RS) or control bagels in high-T2D risk adults (n=24). Fasting and postprandial (with an oral glucose tolerance test) glucose, insulin and HbA1c were measured before and after each bagel treatment. Compared to the control bagel, the RS bagel did not change fasting or postprandial glucose or HbA1c but significantly reduced fasting insulin, 2- and 3-hour insulin iAUC, fasting insulin resistance (HOMA-IR) and beta-cell function (HOMA-%B), and significantly increased fasting insulin sensitivity (HOMA-%S). These results demonstrated that high-RS bagel consumption improves fasting and postprandial insulin sensitivity and provide evidence for a feasible dietary strategy to reduce T2D risk.