Cordon NM, Smart CEM, Smith GJ, et al. - A non-linear association between insulin demand and breakfast carbohydrate content was discovered, implying that strenghtened insulin to carbohydrate ratios (ICRs) are required for meals with ≤ 20g and ≥ 150g of carbohydrate. Dual wave bolusing may be beneficial for meals with ≥ 150g of carbohydrate.

• Thirty-one participants aged 12 to 27 years, HbA1c ≤ 64 mmol/mol (8.0%) received insulin doses based on the individual’s ICR and the study breakfast carbohydrate quantity and then consumed four breakfasts containing 20, 50, 100 and 150 grams of carbohydrate in a randomized order over four consecutive days.

• The highest proportion of time in range was found in the 20 g carbohydrate breakfast.

• Hypoglycaemia was more common in the 50g (n = 13, 42%) and 100g (n = 15, 50%) breakfasts than in the 20 g (n = 6, 20%) and 150 g (n = 7, 26%) breakfasts.

• The 150 g breakfast glucose excursion pattern differed from the smaller breakfasts, with the lowest glucose excursion occurring between 0 and 2 hours and the highest occurring between 3.5 and 5 hours.