Black bean (Phaseolus vulgaris L.) protein hydrolysates reduce acute postprandial glucose levels in adults with prediabetes and normal glucose tolerance

This study evaluated the acute effect of black bean protein hydrolysate (BPH) on postprandial glucose and insulin levels in adults with normal glucose tolerance (NGT) or prediabetes. First, an in silico predictive digestion was performed on twenty peptides identified in BPH. Then, 28 adults with NGT or prediabetes were randomized to a parallel double-blind, placebo-controlled trial. Following consent, participants were randomly assigned to one of two groups, placebo, or 5 g of BPH. To evaluate the acute effects of BPH, an oral glucose tolerance test was administered, and blood samples were collected at 60, 120, and 150 min. In the 5 g BPH group, the area under the curve for glucose, and glucose levels at 120 min were statistically lower compared to the placebo group (p = 0.04, p = 0.02). In this study, BPH had an acute glucose lowering effect after an oral glucose tolerance test in subjects with NGT or prediabetes.