C-Carbs: A CGM-guided Approach to Teaching Carb Awareness

The goal of this randomized study is to learn whether a CGM-guided insulin dosing education program can help adults with diabetes improve how they dose mealtime insulin. The main question it aims to answer is: 1\. Does CGM-guided insulin dosing education improve insulin dosing behaviors and glycemic outcomes in adults with diabetes who do not routinely use carbohydrate counting? Participants will be randomly assigned to either the C-CARBS intervention or usual care. Participants will complete study visits, questionnaires, and meal and insulin logs, and CGM data will be collected to evaluate changes in insulin dosing behaviors and glycemic outcomes.

Inclusion Criteria: * Adults 18 years of age or older. * Diagnosis of diabetes for at least 1 year. * Currently using or willing to start using a continuous glucose monitor (CGM). * Currently using multiple daily insulin injections (MDI). * HbA1c ≥8% at screening/baseline. * Does not routinely use carbohydrate counting or demonstrates poor/inconsistent carbohydrate counting for mealtime insulin dosing. * Able and willing to participate in the study visits and intervention sessions. * Able to provide informed consent. Exclusion Criteria: * Use of an insulin pump or automated insulin delivery system. * Significant medical, cognitive, or psychiatric condition that, in the investigator's judgment, would interfere with participation or completion of study procedures. Limited life expectancy that would prevent completion of the study. * Pregnancy or plans to become pregnant during the study period. * Current participation in another interventional study that could affect diabetes management or study outcomes. * Inability/unwillingess to independently use a CGM device or administer insulin. * Any other condition that, in the investigator's judgment, would make participation inappropriate or interfere with the study's objectives.