Sarah Rice BSc. (Hons), MCOptom (UK), MHP, NNP
November is diabetes awareness month, and while new research on TCR for type 2 diabetes is released almost monthly, the data for type 1 diabetes remains relatively scarce in academic publications. The last few months have seen an upward trend in publications on TCR for type 1 diabetes, bringing much needed attention to this area.
Type 1 diabetes more commonly affects a younger population. It is an autoimmune condition that attacks the pancreatic beta cells and dramatically reduces insulin production. This insulin deficiency results in hyperglycaemia and other symptoms requiring the self-medication of insulin in order to normalise the physiology. Prior to the discovery of insulin, this condition was invariably fatal, marking this breakthrough as a pivotal moment in the treatment of type 1 diabetes. Initially, insulin was administered in conjunction with recommendations to adopt a low-carbohydrate approach, but over time, a more liberal approach gained favour – utilising carbohydrate counting and dosing with insulin (1). Despite advancements in medical technology over time, not only is type 1 diabetes increasing in prevalence, but the majority of those diagnosed fail to meet blood glucose targets set by the various medical establishments (2). A low-carbohydrate dietary approach reduces the amount of insulin dosing at mealtimes (basal insulin is still required) and has been shown to improve glycaemic control.
One population expected to see a significant increase in the development of this condition is the under-15-year-old bracket. Two recent papers explored the use of a low-carbohydrate diet for children and youths compared to other approaches and found it to be safe and effective.
Levran et al. compared a low-carbohydrate (LCD) and Mediterranean diet (MedD) over 6 months. The LCD results were comparable to the MedD but showed more time in range and lower insulin doses for the improved glycaemic control. As higher insulin doses are associated with an increased risk of insulin resistance in the patient with type 1 diabetes, these are important findings (2).
Neuman et al. randomised calorie-matched food box deliveries of a lower carbohydrate (note, not very low carb) of approximately 95 g/day or a recommended carbohydrate diet of approximately 200 g/day. The LCD group showed a significantly higher time-in-range, with less time spent with elevated blood glucose and a lower average blood glucose (3).
In both studies, the LCD groups reported no adverse effects. Taken together, the results suggest that a low-carbohydrate approach is feasible and may confer additional benefits to those with type 1 diabetes.
A new systematic review from Paul et al. examines the effectiveness of the low-carbohydrate approach as represented in the literature and also reports on the lived experiences of adults with type 1 diabetes. An examination of the lived experiences included looking at enablers (motivation and benefits) and barriers (limited information and implementation challenges). Overall, the review was unable to make a definitive statement about the low-carbohydrate approach for effectiveness in improving HbA1c, but it did report that a decrease in HbA1c of ≥0.5% is associated with decreased bolus insulin and weight and an improved quality of life (4). Not everyone found a low-carbohydrate approach easy to follow, so appropriate support via health professionals experienced in this approach could be important for success.
Type 1 diabetes is a challenging condition that requires daily management, where decisions have both immediate and long-term consequences. It is thought that 40–60% of those with type 1 diabetes experience ‘diabetes distress’ as a result of this burden. A case study from Winje et al. reports on an individual with significant symptoms of diabetes distress that fulfilled the diagnostic criteria for phobia (fear of hypoglycaemia and insulin) and depression. The clinical team discussed the benefits of a ketogenic diet as a logical solution to reduce insulin requirements and provided detailed information to ensure the safe implementation of this approach (refer to the paper for details). Within 2 weeks, a steady decrease in blood glucose concentrations and an improved mood began to relieve her symptoms of diabetes distress:
‘In a remarkably short period, I noticed significant improvements. With each passing day, I felt I was regaining my vitality’ (5).
These data highlight the need for more research and education around the role of TCR for the management of type 1 diabetes in order to ensure proper informed consent and support for this approach in the context of an individualised treatment plan.
Find out more
The metabolic section of the Nutrition Network reference resource has an extensive listing where you can read more about the application of therapeutic carbohydrate restriction (TCR) for type 1 diabetes.
Nutrition Network offers training modules where you can learn more about TCR for the management of diabetes for both clinicians and patients.
References
1. Wood M, Ebe K, Bando H. Prolonged Honeymoon Period in Type I Diabetes (T1D) Patients on Low-Carbohydrate Diet (LCD). Asp Biomed Clin Case Rep [Internet]. 2023 Oct 24 [cited 2023 Nov 20];6(3):248–53. Available from: https://asploro.com/prolonged-honeymoon-period-in-type-i-diabetes-t1d-patients-on-low-carbohydrate-diet-lcd/
2. Levran N, Levek N, Gruber N, Afek A, Monsonego-Ornan E, Pinhas-Hamiel O. Low-carbohydrate diet proved effective and safe for youths with type 1 diabetes: A randomised trial. Acta Paediatr. 2024 Oct 16;
3. Neuman V, Plachy L, Drnkova L, Pruhova S, Kolouskova S, Obermannova B, et al. Low-carbohydrate diet in children and young people with type 1 diabetes: A randomized controlled trial with cross-over design. Diabetes Research and Clinical Practice [Internet]. 2024 Nov 1 [cited 2024 Sep 10];217:111844. Available from: https://www.sciencedirect.com/science/article/pii/S016882272400754X
4. Paul J, Jani R, Thorning S, Obucina M, Davoren P, Knight-Agarwal C. Low carbohydrate diets, glycaemic control, enablers, and barriers in the management of type 1 diabetes: a mixed methods systematic review. Diabetology & Metabolic Syndrome [Internet]. 2024 Nov 2 [cited 2024 Nov 4];16:261. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC11531154/
5. Winje E, Lake I, Dankel SN. Case report: Ketogenic diet alleviated anxiety and depression associated with insulin-dependent diabetes management. Front Nutr [Internet]. 2024 Oct 30 [cited 2024 Oct 30];11. Available from: https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2024.1404842/full