Bedtime snacking and glycemic deterioration in young children with Type 1 diabetes on multiple daily injections: a randomized controlled crossover trial

Objective: To determine if a bedtime snack in young children with type 1 diabetes (T1D) prevents nocturnal hypoglycemia, and the impact on glycemia overnight. Methods: In this randomized controlled crossover trial, 10 grams of carbohydrate (milk, yoghurt, and kefir) was given 150–180 minutes after dinner over three nights to 5–8-year-old children with T1D using multiple daily injection therapy. Continuous glucose monitoring (CGM) data were collected for 6 hours following the snacks on one control and three snack nights. Time in 70–180 mg/dL (3.9–10 mmol/L) range (TIR), time below 70 mg/dL (3.9 mmol/L) (TBR), and other metrics were analyzed according to international CGM consensus. Trial day was terminated if blood glucose exceeded 300 mg/dL (16.7 mmol/L) or fell below 70 mg/dL (3.9 mmol/L). Results: Of 28 children (13 female, mean age 6.6 ± 0.8 years, HbA1c 7.0 ± 0.5% (53 mmol/mol)), mean glucose values before the test snacks were 137.8 ± 14.5 mg/dL (7.7 ± 0.8 mmol/L) for milk, 141.9 ± 16.9 mg/dL (7.9 ± 0.9 mmol/L) for yoghurt, 136 ± 19.1 mg/dL (7.6 ± 1.1 mmol/L) for kefir, and 140.8 ± 17.0 mg/dL (7.8 ± 0.9 mmol/L) for control without significant difference (p = 0.548). TIR was 34.7% for milk, 38.7%. for yoghurt, 45.9% for kefir, and 75.5% for control during the 6-hour post snack period, with TIR on the control day significantly higher than the three snack days (p < 0.001). TBR did not differ by group (p > 0.05). Of 112 trial days, 13 days were terminated due to hyperglycemia (>300 mg/dL) (16.7 mmol/L) (8 milk, 4 yoghurt, 1 kefir), and 3 trial days due to hypoglycemia (<70 mg/dL) (3.9 mmol/L) (1 yoghurt, 2 control). Conclusion: Bedtime snacking in young children with T1D impairs nocturnal glycemia and reduces TIR, without decreasing the frequency of hypoglycemia. © The Author(s) 2025.