Specific Collagen Peptides Support Postprandial Metabolic Health by Modulating Incretin Hormones, Gastric Transit, and Glycemic Control in Participants with Normoglycemia and Prediabetes

Background Nutritional preload strategies can improve postprandial glycemic control through modulation of incretin secretion. We previously identified specific collagen peptides (Nextida GC®, hereafter CP) that stimulates glucagon-like peptide-1 (GLP-1) secretion in vitro and improves postprandial glycemic responses in preclinical models and a pilot human study. Objective To investigate the effects of a CP preload on postprandial glycemic control and to characterize the associated hormonal and physiological responses in normoglycemic and prediabetic participants . Methods In a randomized, double-blind, placebo-controlled, crossover study, 30 participants (12 normoglycemic and 18 prediabetic) ingested 10 g CP or placebo 30 minutes before a standardized carbohydrate-rich meal (preload phase). Plasma glucose, serum insulin, C-peptide, GLP-1, and glucose-dependent insulinotropic polypeptide (GIP) concentrations were measured during the preload and postprandial periods. As a potential physiological mechanism gastric transit was assessed via the gastric residence time of an indigestible capsule. Results During the preload phase, CP significantly increased insulin and incretin levels (GLP-1 and GIP) compared with placebo (all p<0.0001). Following the meal, CP significantly reduced postprandial glucose excursions (iAUC 0-180min , p=0.0178), whereas total insulin responses were unchanged (iAUC -30-180min , p=0.8929). Furthermore, CP prolonged gastric residence time of the indigestible 3D-Transit capsule in the prediabetic subgroup (p=0.0436). Conclusions A 10 g preload of CP improved postprandial glycemic control without increasing overall postprandial insulin exposure. These effects were accompanied by early stimulation of insulin and incretin hormones and, in prediabetic individuals prolonged gastric residence time. The findings suggest that CP may support healthy postprandial metabolic regulation through complementary hormonal and physiological mechanisms. Trial registration ClinicalTrials.gov (NCT06789263) https://clinicaltrials.gov/study/NCT06789263?term=NCT06789263&rank=1