Gut microbiome: influence on the clinical and nutritional treatment of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is a complex metabolic disease in whose pathophysiology the gut microbiota plays a key role, influencing systemic inflammation, insulin sensitivity, and glycemic homeostasis, thus conditioning the response to clinical and dietary treatments. The objective of this study was to analyze the influence of the gut microbiota on the pharmacological and dietary treatment of T2DM based on current scientific evidence. This systematic review, conducted according to the 2020 PRISMA guidelines, analyzed 27 studies published between 2014 and 2024, identifying that gut dysbiosis, characterized by a reduction in beneficial bacteria and an increase in pro-inflammatory species, is associated with poorer metabolic control in patients with T2DM. The most effective interventions included probiotics, prebiotics, synbiotics, high-fiber diets, and drugs with microbiota-modulating effects, such as metformin and SGLT2 inhibitors. Evidence suggests that modulation of the gut microbiota represents a promising complementary therapeutic strategy; however, methodological limitations still exist, highlighting the need for more robust clinical studies to support its widespread application.