The efficacy of Diet Therapy vs. Pharmacological Treatment (Medicine) in Adults with Type 2 Diabetes: A Systematic Review

Abstract

Type 2 diabetes mellitus (T2DM) is a global public health challenge characterized by insulin resistance and β-cell dysfunction, potentially leading to increased morbidity and mortality.
A systematic review was conducted following the PRISMA 2020 guidelines. Five electronic databases (PubMed, CINAHL, Cochrane Library, Web of Science, and Google Scholar) were searched for peer-reviewed studies published between 2019 and 2025. Eligible studies included randomized controlled trials, controlled clinical trials, and quasi-experimental studies involving adults with T2DM. Outcomes assessed included glycated hemoglobin (HbA1c), insulin sensitivity, weight, lipid profiles, blood pressure, and medication use. Methodological quality was evaluated using the Academy of Nutrition and Dietetics Evidence Analysis Library (EAL) criteria. The aim was to evaluate the efficacy of dietary therapy compared with pharmacological treatment in improving metabolic outcomes among adults with T2DM.

A total of 11 studies met the inclusion criteria. Dietary interventions, including fasting-based strategies, carbohydrate-restricted diets, plant-based diets, and structured nutrition therapy, consistently improved glycemic control, insulin sensitivity, and weight management. Significant reductions in HbA1c and cardiometabolic risk markers were observed across multiple studies. Remission rates for T2DM ranged from approximately 28% to 54%. Improvements in insulin resistance and β-cell function were identified as key mechanisms underlying metabolic recovery.

Findings support the integration of structured nutrition therapy into standard diabetes care. Early implementation of dietary interventions may enhance the likelihood of reversing metabolic dysfunction and reducing long-term dependence on pharmacological treatment.