Mediterranean diet: can it help children with type 1 diabetes?

Although food and nutrition are foundational in the management of type 1 diabetes (T1D) and the prevention of long-term complications (affecting the eyes, nerves, kidneys, and heart), no specific diet is recommended other than  balanced and varied eating outlined in the Canada Food Guide (2019). But can a certain eating pattern help? A 2022 observational study in Spain investigated the impact of the Mediterranean diet on the blood sugar of children living with T1D, and the results are promising. A small 2023 Israeli study also reports interesting benefits.

Clear evidence shows the importance of adequate blood sugar control after meals in the prevention of long-term complications of diabetes. Despite the influence of food and nutrition on blood sugar management, Canadian nutrition guidelines for people living with T1D are rare for any age, whether a child or an adult.

According to Diabetes Canada, the current guidelines for children living with diabetes are the same as those for children without diabetes: Follow the Canada Food Guide (CFG). While the CFG is an excellent resource, there is a need for research which investigates if different eating patterns (what you eat and drink regularly) impact blood sugar management in children living with T1D. This could help improve nutrition guidelines.

What is the Mediterranean diet?

The Mediterranean diet is not really a “diet” to lose or control one’s weight but a combination of eating patterns from countries located around the Mediterranean Sea. It typically includes plenty of fruits, vegetables, herbs and spices, whole grains, legumes, olive oil, nuts, and fish. It limits red meat and processed foods, instead focusing on whole foods (foods that are as close to their original form as possible, without additives, processing, or artificial substances). Whole foods offer a range of antioxidants and anti-inflammatory effects in the body that improve heart health markers like triglyceride (a type of fat found in blood) and cholesterol levels.

The Mediterranean diet has often been studied among different populations (but though rarely with people living with T1D) and found to reduce the risk of chronic conditions like heart disease and type 2 diabetes. 

Mediterranean diet may improve children’s blood sugar

The 2022 Spanish study looked at the eating habits of 97 children living with T1D in Spain: 71 delivered their insulin through multiple daily injections and 26 used insulin pumps; all were using a continuous glucose monitor (CGM) (e.g. Dexcom, Freestyle Libre 2). The researchers wanted to see if those who ate more in line with the Mediterranean diet had better glucose management than those who did not.

Each participant (and/or their parents) filled out a food questionnaire to see how much their eating habits were similar to the Mediterranean diet. Based on the food questionnaire results, the participants were placed in two groups: those whose eating patterns were closest to the Mediterranean diet, and those whose patterns were not closely aligned with the Mediterranean diet.

The study found that children whose eating pattern was most similar to the Mediterranean diet had:

• Lower HbA1c (average blood sugar levels over three months), 7.2% compared to 7.7%.
• More “Time in Range” (time spent with glucose levels between 4.0 and 10.0 mmol/L), 60.4% compared to 52.1%.

Likewise, an interventional study in Israël, published in 2023, educated 20 adolescents on the Mediterranean diet and asked the participants to adopt the eating pattern. Their blood sugar values were measured before the diet changes and again six months after. The study showed positive results as well: 

• Time in range improved from 52% to 63%;
• Insulin requirements decreased slightly.

What about adults?

There is currently little research that looks at the impact of the Mediterranean diet on diabetes management in adults living with T1D. That being said, the Mediterranean diet has been studied in other contexts among this population. For example, a 2020 Spanish study investigated the impact of the Mediterranean diet on quality of life in adults living with T1D and found that those following a Mediterranean diet were more likely to have a better quality of life than those who did not. Another Spanish study (2019) showed that adults living with T1D tended to eat more closely to the Mediterranean diet than those without diabetes.

All about eating healthy

While future research is still needed to confirm the results of the studies mentioned here, the Mediterranean diet certainly shows promise for children living with T1D. It could become a tool to help improve their blood sugar management. 

In the meantime, the Mediterranean diet has been proven to have many health benefits, especially when it comes to cardiovascular health. This eating pattern could therefore be beneficial for all people living with T1D, who are at a higher risk of cardiovascular disease overall.

Useful resource:

Montreal Hearth Institute  – Mediterranean diet