Differential Modulation of Postprandial Glycemic, Incretin, and Satiety Responses by Low-Digestible Carbohydrates in Humans: An Exploratory Investigation

Background: Effective postprandial glycemic regulation is essential for preventing metabolic disorders such as type 2 diabetes. While pharmacological interventions like GLP-1 (Glucagon-Like Peptide-1) receptor agonists are effective, dietary strategies using low-digestible carbohydrates (LDCs) may offer a sustainable and complementary approach. Methods: Two human physiological investigations were conducted to evaluate the acute metabolic responses to allulose, 1-kestose, resistant maltodextrin (RD), and fructo-oligosaccharide powder (FOP), administered both in isolation and in conjunction with a reference meal (RM). Results: In Study 1, all tested LDCs elicited minimal plasma glucose responses when consumed alone. In Study 2, distinct metabolic benefits were observed depending on the type of LDCs. Allulose exhibited the strongest effects, significantly reducing postprandial glucose and insulin levels while increasing plasma GLP-1 concentrations. 1-Kestose exhibited significantly lower plasma glucose and insulin incremental area under the curve (iAUC) compared to RM alone, indicating improved glycemic regulation. RD significantly enhanced subjective satiety between 30 and 180 min post-consumption. These findings highlight that each LDC exerts unique physiological effects. Conclusions: Collectively, these results demonstrate that acute LDCs consumption distinctly regulates metabolic responses, supporting their application as functional ingredients in targeted nutritional strategies for managing glycemic and metabolic health.