2.3. Study Procedures
T1D, ’ fasting blood, hypoglycemia, hyperglycemia
HYPOGLYCEMIA, HYPERGLYCEMIA, EVENT, INSULIN SENSITIVITY
During a first screening visit, participants’ fasting blood, urine, and anthropometrical measurements were taken. After screening and before the first test meal occasion, they were instructed to complete a 3-day diary including capillary blood glucose measurements when fasting in the morning, before and 2 h after each meal, and before bedtime. This was used to optimize insulin doses for the T1D group. All participants used rapid-acting insulin analogs for their meal doses (35% insulin lispro and 65% insulin aspart). Capillary blood glucose measurements (at least seven) were also recorded for the 24 h before each testing occasion. Each participant was assigned to a random sequence of meals, which was generated by a computer software (On the day of the test meal, a standardized breakfast (ca. 420–440 kcal, 58% of energy intake from carbohydrates, 22% from protein, and 20% from fat) was eaten four hours before the test meals to prevent differences due to any remaining breakfast effects. In the event of hypoglycemia during the 4 h period before the meal or during testing, the participants were instructed to correct it as per usual management, with dextrose tablets (3 g carbohydrates/tablet) being the first-line treatment recommendation. The amount of food consumed for the correction of hypoglycemia, which did not exceed 20 g carbohydrates, was noted, and then used as a covariate in the statistical analysis models (see statistical analysis).The test meals were served at approximately 11.00 am. Participants were instructed to abstain from any physical activity between breakfast and the test meal. The recommended meal insulin doses were calculated based on carbohydrate counting using a standard insulin-to-carbohydrate ratio (ICR); if needed, participants took a small correction dose for hyperglycemia based on their insulin sensitivity factor (ISF) and adjusted the recommended dose according to their personal experience of similar meals. The postprandial testing period was four hours, during which participants were seated and engaged only in sedentary activities.