by Lucía Feito Allonca 

In this post I will discuss two recent studies on the treatment of diabetes with a low carbohydrate diet.

Firstly, a study by the Spanish Diabetes Society where the conclusion was clear: that low-carbohydrate eating coupled with the use of technology is beneficial for diabetes management, and secondly, a recent study on low-carbohydrate diets in children and adolescents living with or at risk of developing diabetes.

Low carb diet + Closed Loop Systems: Better glucose management

In a recent study conducted by the Spanish Society of Diabetes (SED), it was found that even though up to 66% of patients with type 1 diabetes (T1D) were following a diet considered balanced, only a third of them were able to maintain an HbA1c level below 7%. Additionally, around 40% of T1D patients were overweight or obese. This raises the question of whether the conventional diet recommended for these patients is the most suitable and whether there are alternatives to achieve better therapeutic outcomes.

In the 2020 update of the American Diabetes Association (ADA) guidelines, low-carbohydrate diets were included as one of the healthy dietary options.

In T1D patients using closed-loop insulin infusion systems (hybrid closed-loop systems), it has been observed in a retrospective observational study at the Vall d’Hebron Hospital in Barcelona that combining a low-carb diet with this technology can lead to more stable blood sugar control, especially during the night when there are fewer external stimuli. 

Low Carb Diets in Children and Adolescents with or at risk of diabetes

The present study is very recent and dates from 18 September 2023. It examines the use of a low-carbohydrate diet as a tool for weight loss and management of type 1 and type 2 diabetes.

It highlights the fact that the pediatric population in the United States faces a serious problem: obesity, and that its prevalence is increasing. It is noted that low-carbohydrate diets have been used for decades in adults to improve metabolic health and treat diabetes.

Current dietary recommendations for children and adolescents with type 1 diabetes reflect those of the general population. It is common to dose insulin at mealtimes according to the amount of carbohydrate to be eaten. People with type 1 diabetes may use low-carbohydrate diets to facilitate the reduction of exogenous insulin requirements and reduce mealtime blood glucose excursions. 

However, although we are aware of success stories, there are very few data on the use of very low-carbohydrate or ketogenic diets in children and adolescents with type 1 diabetes. A study in adults with type 1 diabetes showed a decrease in insulin requirements.

A survey was conducted with an international social network-based group of adults with type 1 diabetes and parents of young people with type 1 diabetes who choose to use low or very low carbohydrate diets as an adjunctive treatment. Respondents reported excellent glycaemic control, but a poor relationship with diabetes professionals associated with mistrust and a feeling of being judged for their diabetes management decisions.

The study notes that there is clinical consensus to support lower carbohydrate intake and higher quality protein and fat intake in young people under medical supervision, if this is their choice and they have family and medical support, open dialogue about diabetes management decisions, dietary habits and choices, and regular medical follow-up with a supportive multidisciplinary team, including a pediatric dietitian.

Type 2 diabetes results from resistance to the physiological action of insulin in muscle and liver and progressive failure of pancreatic β-cells leading to relative insulin deficiency. Treatment requires addressing insulin resistance and insulin deficiency. Reducing carbohydrate can be an important and effective part of the overall management of type 2 diabetes, as it reduces insulin resistance and the demand for increasing amounts of insulin by the pancreas. As with people with type 1 diabetes, people with type 2 diabetes who use exogenous insulin for treatment can follow low-carbohydrate diets to lower blood glucose values and reduce exogenous insulin requirements.

Moderate or low-carbohydrate diets in adults with type 2 diabetes are beneficial for blood glucose and cardiovascular disease risk.

The final conclusions are as follows:

• Low-carbohydrate (<26% energy) and very low-carbohydrate (20-50g) diets are not recommended for children and adolescents with type 1 diabetes, except under close supervision of a diabetes care team.

• For the prevention and treatment of pre-diabetes and type 2 diabetes, it is recommended to reduce intake of nutrient-poor carbohydrates by minimising consumption of processed foods with large amounts of refined grains and added sugars and eliminating sugar-sweetened beverages.

• Eliminating sugary drinks and juices significantly improves blood glucose and weight control in children and adolescents.

Although the recent news headline "Low-carbohydrate diets are not recommended for children" is often published, it does not tell the whole story.

It is still possible for us as a family to decide that a diet that reduces carbohydrate intake is the approach we want to take to avoid dangerous glycaemic excursions in our children and adolescents.

With the supervision of our health care team, and regular check-ups, we can arrive at the diabetes management outcomes we want, for ourselves and our loved ones.