Resistant Starch Type ۳ and Lactobacillus plantarum: Mechanisms of Action in Postprandial Glucose Control for Prediabetic Individuals

Prediabetes affects approximately ۹% of adults globally and represents a critical window for preventing progression to type ۲ diabetes mellitus through dietary interventions. This narrative review synthesizes current evidence on the mechanistic pathways and clinical potential of resistant starch type ۳ (RS۳) and Lactobacillus plantarum (L. plantarum) in postprandial glucose regulation among prediabetic individuals. RS۳, a retrograded starch formed through cooking and cooling processes, resists small intestinal digestion and undergoes colonic fermentation, generating short-chain fatty acids that modulate gut hormone secretion, enhance insulin sensitivity, and attenuate postprandial glycemic excursions. L. plantarum, a well-characterized probiotic strain, improves glucose homeostasis through complementary mechanisms including enhancement of intestinal barrier integrity, reduction of metabolic endotoxemia, modulation of bile acid and glucose transporter expression, and production of bioactive metabolites. Clinical evidence demonstrates that RS۳ supplementation (≥۲۰ g/day) reduces postprandial glucose peaks by approximately ۱.۰-۱.۵ mmol/L, while L. plantarum HAC۰۱ (۴×۱۰° CFU/day for ۸ weeks) significantly lowers ۲-hour postprandial glucose and HbA۱c levels in prediabetic adults. The synergistic combination of RS۳ and L. plantarum offers theoretical advantages through complementary metabolic pathways, with RS۳ serving as a prebiotic substrate that selectively stimulates probiotic activity and enhances short-chain fatty acid production. However, direct human trials investigating this synbiotic combination remain lacking. Practical implementation strategies include incorporating cooked-and-cooled starchy foods (rice, potatoes, pasta, legumes) and fermented plant foods or standardized probiotic supplements into culturally adapted meal plans. Despite promising mechanistic and preliminary clinical evidence, substantial knowledge gaps persist regarding optimal dosing regimens, long-term efficacy, inter-individual response variability, and potential interactions with antidiabetic medications. This review highlights the need for large-scale, well-controlled randomized trials specifically evaluating RS۳-L. plantarum synbiotic formulations in prediabetic populations to establish evidence-based nutritional strategies for postprandial glucose management and diabetes prevention.

Keywords:

Lactobacillus plantarum , prediabetes , postprandial glucose , gut microbiota , synbiotics