IMPACT OF THE KETOGENIC DIET ON GLYCEMIC CONTROL: A SYSTEMATIC COMPARATIVE REVIEW OF THE LOW-CARBOHYDRATE DIET AND STANDARD DIABETIC DIET IN PATIENTS WITH TYPE 2 DIABETES MELLITUS
DOI:
https://doi.org/10.31435/ijitss.2(50).2026.5680Keywords:
Ketogenic Diet, Type 2 Diabetes Mellitus, Glycemic Control, HbA1c, Nutritional Ketosis, Low-Carbohydrate DietAbstract
Research Objectives: This systematic review aimed to evaluate whether the ketogenic diet (KD) offers a safe and effective pathway to clinical remission in type 2 diabetes mellitus (T2DM), compared to non-ketogenic low-carbohydrate diets and standard diabetic care. Specifically, we sought to assess the impact of KD on glycemic control, weight loss, cardiovascular risk factors, and the need for glucose-lowering medications.
Methods: Following PRISMA 2020 guidelines, we conducted a comprehensive literature search in PubMed, MEDLINE, and Embase for studies published between 2000 and 2025. Nineteen core reports from randomized controlled trials and intensive clinical programs were selected for review based on relevance and methodological quality.
Key Findings: In the short term (3 to 6 months), the KD was associated with significantly greater reductions in glycated hemoglobin (HbA1c) - typically between 0.8% and 1.5%, and more substantial weight loss than standard dietary approaches. While long-term glycemic outcomes (12 to 24 months) tended to align with other intensive interventions, the KD distinguished itself by enabling rapid deprescription of glucose-lowering medications, including insulin and sulfonylureas. Patients also showed consistent improvements in cardiovascular risk markers, such as lower triglycerides and higher HDL cholesterol. Safety data revealed no evidence of adverse effects on renal or hepatic function; on the contrary, many participants experienced improved liver enzyme profiles and stable kidney function markers.
Conclusions: The ketogenic diet appears to be a safe and effective metabolic strategy for patients with T2DM, delivering superior short-term glycemic control, weight loss, and medication reduction. These benefits suggest the KD may facilitate clinical remission in selected individuals with T2DM.
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Copyright (c) 2026 Zofia Julia Parol, Mateusz Żyła, Aleksandra Ustaszewska, Aleksandra Oszczypała, Aleksandra Potempa, Michał Petkow, Liwia Prorok, Katarzyna Lipska, Monika Szyszkowska, Zuzanna Strojek
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