Patient description: The patient is a 24-year-old man who has had type 1 diabetes for 11 years. He presents to the emergency room with hyperglycemia and concern for possible diabetic ketoacidosis after not taking his insulin for 3 days. The patient reports that he is currently homeless and has lost his supply of insulin, syringes, glucometer, and glucose testing supplies. The patient states that at the time of his initial diagnosis with type 1 diabetes he was hospitalized with a glucose value >1000 mg/dL. At the time, he was experiencing polyuria, polydipsia, and polyphagia. He reports that he has been on insulin since the time of his diagnosis, and he has never been prescribed oral agents for diabetes management. Most recently, he has been using insulin glargine 55 units once daily, and insulin aspart sliding scale 3 times daily. The patient has had previous episodes of diabetic ketoacidosis, for which he was hospitalized. With this episode of hyperglycemia, he is not experiencing any nausea, vomiting, or abdominal discomfort, and he appears well. His lab studies showed: A1c: 11.3% Creatinine: 0.9 mg/dL with eGFR >60 mL/min Aspartate aminotransferase (AST): 17 U/L Alanine aminotransferase (ALT): 14 U/L Beta-hydroxybutyrate: 0.1 mmol/L Bicarbonate: 25 mEq/L Anion

Clinical trial eligibility criteria: eligible ages (years): 18.0-999.0,  Type 1 Diabetes Mellitus Clinical diagnosis, based on investigator assessment, of type 1 diabetes for at least one year and using insulin for at least 1 year Using an insulin pump for at least 3 months at the time of screening. Insulin pump use includes use of automated features, to predictive or threshold low-glucose suspend or hybrid closed-loop with without a Dexcom sensor Familiarity and use of a carbohydrate ratio for meal boluses Age ≥18.0 years old HbA1c < 10.5%, as performed by point of care or central laboratory testing. A1c will be assessed at the screening visit, or if already completed within 2 weeks of the screening visit, the prior lab value may be used in lieu of repeating this assessment For females, not currently known to be pregnant. If female and sexually active, must agree to use a form of contraception to prevent pregnancy while a participant in the study. A negative serum or urine pregnancy test will be required for all females of child-bearing potential. Participants who become pregnant will be discontinued from the study. Also, participants who during the study develop and express the intention to become pregnant within the timespan of the study will be discontinued Willingness to switch home pump to PLGS or full manual mode if using hybrid closed-loop with an FDA approved system Have an emergency contact living at home with the subject who will be available to be contacted by the study staff overnight in the event of an emergency Investigator has confidence that the participant can successfully operate all study devices and is capable of adhering to the protocol, to having basic cooking equipment at home to prepare the study meals Willingness to switch to lispro (Humalog) or aspart (Novolog) if not using already, and to use no other insulin besides lispro (Humalog) or aspart (Novolog) during the study  Use of an unapproved closed-loop insulin delivery system within 2 weeks before screening or during the study is not allowed Gastrointestinal disease such as celiac disease or multiple food allergies Any form of gluten sensitivity or wheat allergy Allergies to any form of nuts or ingredients present in the study meals (tomatoes etc) History of difficulty digesting food Concurrent use of Afrezza or any non-insulin glucose-lowering agent other than metformin (including GLP-1 agonists, Symlin, DPP-4 inhibitors, SGLT-2 inhibitors, sulfonylureas) Hemophilia or any other bleeding disorder One or more episodes of hypoglycemia requiring an emergency room visit or hospitalization in the past 6 months One or more episodes of hyperglycemia requiring an emergency room visit or hospitalization in the past 6 months Self-reported or clinically documented hypoglycemia unawareness