The purpose of this study is to measure the metabolic phenotype of a range of body weights in individuals with and without type 1 diabetes.

Inclusion Criteria:

1. Males and females, 19 to 30 years of age, inclusive.

2. Type 1 Diabetes Cohort:

   1. Diagnosis of type 1 diabetes for greater than 1 year at screening.
   2. Hemoglobin A1c 6.5-13% or

   Control Cohort Without Diabetes:

   a. Healthy individuals without diabetes matched to T1D cohort by BMI and gender

3. Able to provide informed consent.

4. BMI 18-39.9 kg/m^2

Exclusion Criteria:

1. Type 2 diabetes
2. History or presence of cardiovascular disease (unstable angina, myocardial infarction or coronary revascularization within 6 months, clinically significant abnormalities on EKG, presence of cardiac pacemaker, implanted cardiac defibrillator)
3. Liver disease (AST or ALT >2.5 times the upper limit of normal), history of hepatitis
4. Kidney disease (creatinine >1.6 mg/dl or estimated glomerular filtration rate (GFR)<60 ml/min)
5. Dyslipidemia, including triglycerides >800 mg/dl, LDL >200 mg/dl
6. Anemia (hemoglobin <12 g/dl in men, <11 g/dl in women)
7. Thyroid dysfunction (suppressed thyroid-stimulating hormone (TSH), elevated TSH <10 µIU/ml if symptomatic or elevated TSH >10 µIU/ml if asymptomatic)
8. Uncontrolled hypertension (BP >160 mmHg systolic or > 100mmHg diastolic)
9. History of cancer within the last 5 years (skin cancers, with the exception of melanoma, may be acceptable).
10. Initiation or change in hormone replacement therapy within the past 3 months (including, but not limited to thyroid hormone, birth control or estrogen replacement therapy)
11. History of organ transplant
12. History of HIV, active Hepatitis B or C, or Tuberculosis
13. Pregnancy, lactation or 6 months postpartum from screening visit
14. History of major depression
15. Psychiatric disease prohibiting adherence to study protocol
16. History of eating disorders
17. Cushing's disease or syndrome
18. History of bariatric surgery
19. Tobacco use within the past 3 months
20. History of drug or alcohol abuse (≥3 drinks per day) within the last 5 years
21. Use of oral or injectable anti-hyperglycemic agents (except insulin)
22. Current use of beta-adrenergic blocking agents
23. Use of antibiotics within the past 3 months
24. Weight >450 lbs (This is DEXA table weight limit)
25. Metal implants (pace-maker, aneurysm clips) based on Investigator's judgment at screening
26. Unable to participate in MRI or magnetic resonance spectroscopy (MRS) assessment based on Investigator's judgment at screening
27. Participants with strict dietary concerns (e.g. vegetarian or kosher diet, multiple food allergies, or allergies to food we will provide them during the study)
28. Gastrointestinal disorders including: inflammatory bowel disease or malabsorption, swallowing disorders, suspected or known strictures, fistulas or physiological/mechanical GI obstruction, history of gastrointestinal surgery, Crohn's disease or diverticulitis.
29. Presence of any condition that, in the opinion of the investigator, compromises participant safety or data integrity or the participant's ability to complete study visits

Young adults with type 1 diabetes diagnosed greater than or equal to 1 year prior to screening, or control young adults without diabetes, both within a range of BMI classifications (18-39.9 kg/m^2).

28-42 days