Effect of Different Carbohydrate Intake Patterns on Glycemic Control in Patients With Type 1 Diabetes

This multicenter, randomized, controlled, open-label clinical trial aims to evaluate the effects of different carbohydrate intake patterns on glycemic control in adults with type 1 diabetes. Participants will first complete a 2-week run-in period and will then be randomly assigned in a 1:1 ratio to one of two dietary groups. Both diets provide similar proportions of total energy from carbohydrates, protein, and fat, but differ in the sources of staple carbohydrates. In the moderate carbohydrate diet group, most staple foods are refined grains, whereas in the diverse carbohydrate diet group, approximately half of the staple foods are whole grains and legumes. 80 participants will follow the assigned dietary intervention for 2 weeks, followed by a 12-week follow-up period. The primary outcome is time in range (TIR), defined as the percentage of time that glucose levels are within the target range, measured using continuous glucose monitoring. Other measures of glycemic control, glycemic variability, insulin requirements, body measurements, metabolic indicators, and safety will also be evaluated. Exploratory analyses will assess potential changes in gut microbiota, immune function, and metabolomic profiles.