Implementing a low-carbohydrate diet in adults to manage type 1 diabetes mellitus: a standard of care protocol

Amanda A. Felizardo, Caroline D. S. B. Paiva, Jordana D. F. L. Brasileiro, Mariana S. D. D. Souza, Rúbia M. Corrêa, Dayse R. D. Carvalho, Maria V. C. D. Abreu, Laryssa R. D. S. Franckilin, Roberta D. M. V. D. Assis, Francisco D. A. D. M. Martins Júnior, Daniela D. G. Neri, Janaína Fonseca Koenen, Giselle Foureaux


Background: Type 1 diabetes mellitus is an autoimmune disease characterized by the destruction of pancreatic beta cells and absolute insulin deficiency. After the discovery of insulin, guidelines recommended 50% to 60% of carbohydrate consumption in individuals with diabetes. However, this recommendation is ineffective, since carbohydrate is the macronutrient that causes the greatest increase in blood glucose. The aim of this research is to evaluate the efficacy of a low-carbohydrate diet in adults with type 1 diabetes mellitus.

Methods: The study is a 26 weeks clinical trial. During the first 15 days, participants will receive approximately 130 g of daily carbohydrates, followed by a phase of 7 days, with the consumption of 90 g of daily carbohydrates, and finally, the consumption of 50 g of carbohydrates. The target audience is 20 participants diagnosed with type 1 diabetes mellitus, glycated hemoglobin (HbA1c) >7.0% and aged between 21 and 50 years, in addition to the parameters defined in the established inclusion and exclusion criteria. The primary outcome is HbA1c. Glycemic variability, frequency of hypoglycemia, total daily insulin and improvement in quality of life will also be evaluated.

Conclusions: Despite the evidence that low carbohydrate is effective for treating type 2 diabetes, there is low evidence for the recommendation in people with type 1 diabetes. In order to improve quality of life of this group and guidelines of clinical practice, and to promote development of health care professionals, further well-designed trials are needed.

Trial registration: The trial was registered at


Type 1 diabetes mellitus, Low-carbohydrate diet, Glycemic control

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