This study aimed to assess the body composition of pediatric patients with type-1 diabetes (T1D) in a Portuguese pediatric endocrinology/diabetic clinic, using the InBody 570 bioimpedance system. Preschool children (<6 years) and those recently diagnosed (<6 months) were excluded.

The study included 78 patients (53% female). Median age at assessment was 14 years, with 81% pubertal children. Eighty-seven percent were using continuous subcutaneous insulin infusion (CSII), 25% with an automated closed-loop model. Median HbA1c was 7.3%. Most had an adequate body mass index (BMI) standard deviation score (62%) and 48% engaged in regular physical exercise (PE) outside of school. Median percentage body fat (PBF) was 21.5% and was abnormal in 48%, with median visceral adiposity of 4. Despite adequate BMI, 11% had excessive PBF. PBF was significantly associated with visceral fat (r=0.79; P<0.001), female gender (P<0.001) and PE performed out of school (P=0.005). PE was associated with lower PBF (P=0.005), lower visceral fat (P=0.002), and higher muscle-to-fat ratio (P=0.006).

Engaging in physical exercise out of school correlated significantly with improved body composition, characterized by reduced PBF and diminished visceral adiposity. Considering the known benefits of physical exercise for metabolic and glycemic control, this study highlights the importance of promoting regular physical exercise in T1D patients.