Diet and Insulin Management Technology Show Most Consistent Benefits for Type 1 Diabetes

The most consistent benefits for adults with type 1 diabetes (T1D) can be seen with a combination of a low-carbohydrate diet, education, carbohydrate counting, and modern diabetes technology, such as insulin doses and delivery systems. Investigators noted that the Mediterranean diet and plant-based diets support psychological well-being, although current evidence still remains limited.¹

“The reviewed studies collectively explored a broad spectrum of metabolic outcomes, including HbA1c, [continuous glucose monitoring] CGM-based indices, lipid profile, and anthropometric measures,” the study authors said.¹ “Such comprehensive assessment allows for a multidimensional interpretation of dietary intervention effects in adults with type 1 diabetes.”

Pharmacists play a large role in diabetes care for patients, especially with advancements in technology. Glucose monitoring is essential for patient-centric care, as it helps to personalize treatment and assess the achievement of glucose targets. Continuous glucose monitoring (CGM) has emerged as one of the most effective methods for managing blood glucose for both type 2 diabetes and T1D. Successful usage often hinges upon the patient’s education, which largely comes from pharmacists.²

“Pharmacists are already engaged in diabetes education across various settings, such as community pharmacies, hospitals, and clinics, and their role is expanding to encompass assisting patients with CGM devices,” investigators of a study published in the Journal of Pharmacy Technology said.²

In the review published in Nutrients, investigators included studies within the last 10 years to reflect the major technological advancements, such as CGMs, and structured their search around population, dietary interventions, and clinical and psychosocial outcomes. There were 4437 records identified, with 2054 duplicates and 2049 being excluded. A total of 334 were eligible for full-text analysis, with 301 being excluded due to not meeting the criteria. A total of 41 were included, with 18 being observational, 14 being randomized controlled trials, and 9 being psychosocial determinants.¹

Publications were mainly published in Europe and North America, with some published in South America and Asia, and were published between 2015 and 2025. In total, there were approximately 12,860 adult patients with T1D, with 8682 from observational analyses, 648 from randomized controlled trials, and 3532 from psychosocial studies, according to the authors. In all studies, the low-carbohydrate diet and systematic carbohydrate counting were the most effective strategies for improving glycemic control and reducing insulin requirements. However, the Mediterranean diet and plant-based diet were associated with better food quality and overall well-being.¹

“Despite differences in design and follow-up, the evidence suggests that diet quality, CHO [carbohydrate] and protein intake, nutrition education, and technology-enabled self-management are key determinants of GC [glycemic control] and metabolic well-being in the study population,” the study authors said.¹

Within the observational analyses, low-carbohydrate diets increased the likelihood of maintaining hemoglobin A_1c (HbA_1c) of 7% or less by 2.75, and glycemic control increased by 3.27. For randomized controlled trials, low-carbohydrate diets reduced HbA_1c, an average of 0.65%. Furthermore, the use of a bolus calculator improved HbA_1c by 5 mmol/mol compared with 2 mmol/mol with manual calculations. Low-carbohydrate and high-protein diets also reduced the frequency of hypoglycemia. Further, investigators noted that vegan and Mediterranean interventions were associated with moderate weight loss and a reduction of insulin dosage by approximately 15% to 20%, but for lipid profile and blood pressure, these diets only had minimal changes.¹

“Overall, individualized therapy that combines CHO control, education, and technology (CGM and automated insulin delivery) is the operational core of effective nutritional care in T1D,” the study authors said. “Reduced insulin requirements are the most common and durable effect; however, variability in glycemic responses and potential risks (HypoG [hypoglycemia], dyslipidemia, micronutrient deficiencies) require individual monitoring.”

REFERENCES

1. Sperkowska BM, Chrustek A, Gryn-Rynko A, Proszowska A. Dietary Interventions for Adults with Type 1 Diabetes: Clinical Outcomes, Guideline Alignment, and Research Gaps-A Scoping Review. Nutrients. 2025 Oct 24;17(21):3349. doi: 10.3390/nu17213349. PMID: 41228423; PMCID: PMC12609816.

2. Gamal Eldin A, Nogid A. Integrating Continuous Glucose Monitoring Into Pharmacy Elective Curriculum: A Practical Learning Experience. J Pharm Technol. 2025 Oct 17:87551225251379742. doi:10.1177/87551225251379742. Epub ahead of print. PMID: 41113281; PMCID: PMC12534835.