The purpose of this research study is to understand how type 1 diabetes (T1D) increases the risk for cardiovascular diseases (heart attack and stroke). To this end, the investigators will compare apolipoprotein and triglyceride kinetics in people wtih T1D and healthy control participants.

Not required

Inclusion Criteria:

• Age: ≥18 but ≤45 years
• premenopausal/eumenorrheic and not pregnant or breastfeeding
• non-obese (body mass index ≥18.5<30.0 kg/m2)
• Fasting plasma triglyceride <150 mg/dL

Additional inclusion criteria for control subjects:

• Fasting plasma glucose <100 mg/dL
• Plasma glucose 2 h after a 75 g oral glucose challenge <140 mg/dL
• HbA1c <5.6%.

Additional inclusion criteria for subjects with T1DM:

• stable insulin regimen (multiple daily insulin injections or continuous subcutaneous insulin) for at least 8 weeks before screening
• no use of diabetes medications other than insulin
• HbA1c <8.0%, basal (overnight fasted)
• no severe symptomatic hypoglycemic event associated with a seizure or requiring help from other people or a medical facility in the 6 months prior to screening or metabolic testing

Exclusion Criteria:

• more than 1.5 h of structured exercise/week
• use of tobacco products, excessive amounts of alcohol, or dietary supplements and/or medications known to affect lipid metabolism
• hypothyroidism or other disorders known to affect lipid metabolism
• conditions that would make it impossible to complete the study protocol

De-identified data will be available upon reasonable request

5 years after completion of the study