MECHANISMS AND CLINICAL EFFICACY OF SOLUBLE DIETARY FIBER IN GLYCEMIC CONTROL: A NARRATIVE REVIEW
Main Article Content
Abstract
Aims: This review aims to synthesize the physiological mechanisms and evaluate the clinical efficacy of soluble dietary fiber (SDF) in glycemic management for patients with prediabetes and type 2 diabetes. It specifically focuses on clinical application guidance based on the physiological characteristics of different fiber groups.
Methods: A narrative review approach was employed to aggregate and analyze data from major medical databases (PubMed, Cochrane Library, ScienceDirect). The review prioritizes meta-analyses and randomized controlled trials (RCTs) published between 2023 and 2025.
Results: The therapeutic efficacy of SDF is heterogeneous and strictly contingent upon its physicochemical properties. High-viscosity fibers (e.g., β-glucan, Psyllium) act primarily through physical mechanisms by forming a gel matrix that delays gastric emptying and hinders digestive enzymes, significantly reducing postprandial glucose and HbA1c levels. Conversely, fermentable fibers (e.g., Inulin, FOS) operate via endocrine pathways, producing short-chain fatty acids (SCFAs) that stimulate incretin hormones (GLP-1) to enhance long-term insulin sensitivity. Clinical outcomes are further modulated by inter-individual variability and gut microbiota composition.
Conclusion: Soluble dietary fiber represents a safe adjunctive nutritional therapy. To optimize outcomes, practitioners may consider a shift toward personalized nutrition; it is suggested to prioritize high-viscosity fibers and implement food sequencing strategies (consuming fiber before carbohydrates), adjusted for individual tolerance.
Keywords
Soluble dietary fiber, type 2 diabetes mellitus, glycemic control, viscosity, gut microbiota.
Article Details
References
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