Gut-targeted dietary FIBER interventions in type 2 and gestational diabetes: Mechanisms and clinical evidence

Abstract:

Diabetes mellitus is a major global health burden, with type 2 diabetes mellitus (T2DM) and gestational diabetes mellitus (GDM) accounting for a substantial proportion of metabolic morbidity. While pharmacological therapies remain central to management, increasing attention has been directed toward dietary fiber as an adjunct strategy due to its effects on glycemic regulation and gut microbiota modulation. Evidence from randomized controlled trials and meta-analyses indicates that higher dietary fiber intake is associated with clinically meaningful reductions in glycated hemoglobin, fasting plasma glucose, and insulin resistance in individuals with T2DM, while improving glycemic stability and reducing insulin requirements in GDM. These benefits are mediated through delayed carbohydrate absorption, enhanced short-chain fatty acid production, incretin hormone secretion, and improvement of gut barrier integrity. This review synthesizes current mechanistic and clinical evidence on dietary fiber interventions in T2DM and GDM, highlighting shared and condition-specific pathways, translational challenges, and emerging opportunities for precision nutrition. A gut-targeted approach to fiber intake may represent a cost-effective and sustainable strategy for improving metabolic outcomes across the life course.