The Mediterranean Diet for Adolescents with Type 1 Diabetes: A Prospective Interventional Study

The Mediterranean diet (MED) is highly recommended. Medical nutrition therapy is the cornerstone of diabetes treatment. The primary outcome was to evaluate the change in micronutrient intake of youth with type 1 diabetes before and after a 6-month MED intervention; we also assessed adherence and glycemic control. Twenty adolescents, median age 18 years (interquartile range: 15.5-21), median diabetes duration 9 years (7-14), using continuous glucose monitoring devices, received personalized diet regimes based on MED. At 6 months post-intervention, the caloric intake remained unchanged; however, the carbohydrate proportion was lower (p = 0.058), and the intakes of some monounsaturated fats increased (p = 0.049). Sodium intake exceeded the recommended daily allowance by 250% (p = 0.653), before and after the intervention. For blood glucose, the percent TIR (time-in-range, 70-180 mg/dL) improved from 52% (38-60) to 63% (47-71) (p = 0.047). The total insulin dose decreased marginally, from 0.76 u/kg (0.64-0.97) to 0.72 u/kg (0.61-0.89) (p = 0.067). BMI z-score and waist circumference did not change (p = 0.316 and p = 0.161, respectively). Diastolic blood pressure percentile decreased from 73% (68-88) to 69% (50-79) (p = 0.028), and LDL cholesterol from 114 mg/dL (105-134) to 104 mg/dL (96-124) (p = 0.059). The Israeli Mediterranean diet screener score increased, from 8 (7-11) to 13 points (12-14) (p < 0.001). The MED-based intervention in youth with type 1 diabetes is feasible and leads to improvement in monounsaturated fat intake, TIR, and diastolic blood pressure. Other parameters show no change (caloric intake, BMI, and HbA1c).