Type 1 Diabetes Management Using a Very Low Carbohydrate Versus Standard Diet
Type 1 Diabetes Management Using a Very Low Carbohydrate Versus Standard Diet
Despite major technological advances, management of type one diabetes mellitus (T1D) remains
 suboptimal, putting millions of people at risk for immediate and long-term complications.
 After meals, a mismatch between carbohydrate absorption rate and insulin action typically
 leads to alternating periods of hyper- and hypoglycemia. A conceptually promising approach to
 control both problems is dietary carbohydrate restriction to reduce postprandial blood
 glucose changes and insulin needs. In a prior survey study, the investigators documented
 exceptional glycemic control (HbA1c 5.67%) and low acute complication rates among 316
 children and adults with T1D consuming a very-low-carbohydrate diet.

 To test the feasibility of this approach, the investigators will conduct a
 randomized-controlled feeding study involving 32 adults and adolescents with T1D.
 Participants will be randomized to receive a very low carbohydrate vs. standard carbohydrate
 diet. Participants will be in the study for 12 weeks and receive all their meals by meal
 delivery.They will share continuous glucose monitoring data with the study team and be in
 close communication to adjust insulin doses as needed. All participants will have a screening
 visit, an individual or group education session, and 7 study visits with fasting blood draws
 to evaluate diabetes control and metabolic health. Two of the visits will also comprise
 additional metabolic studies to assess glucagon response and brain function during
 hypoglycemia by magnetic resonance imaging (MRI). Participants will have IV catheters placed
 and receive IV insulin to drop blood glucose levels to 50 mg/dl for up to 30 minutes. The
 primary outcome will be HbA1C change from baseline. Secondary outcomes include detailed
 measures of glycemic variability, metabolic health, and quality of life.
Inclusion Criteria:

 -  Males and females with T1D for at least 1 year

 -  Age 18 to 30 years

 -  Tanner stage ≥ IV

 -  BMI 18.5-30 kg/m2

 -  Stable glycemic control (HbA1c 7-9%)

 -  Use of a continuous glucose monitor (CGM)

 -  Use of an insulin pump

 -  Attendance of at least 3 diabetes care visits over the past 12 months

 Exclusion Criteria:

 -  Ketoacidosis or severe hypoglycemia with seizure or coma in the past year

 -  Dietary restrictions or intolerances that are incompatible with the planned food
 deliveries, e.g. celiac disease, gastroparesis, certain food allergies

 -  Following a weight-loss or otherwise restrictive diet

 -  Use of medications or supplements other than insulin to control blood glucose

 -  Vigorous exercise >2 hours on >3 days a week

 -  History of an eating disorder or at risk for eating disorder, assessed by the Eating
 Disorders Diagnostic Scale (EDDS)

 -  Major medical illness or use of medications that could interfere with metabolic or
 glycemic variables

 -  Significant psychiatric illness or use of psychotropic medication

 -  Smoking, use of recreational drugs, or excessive alcohol consumption

 -  Pregnancy or breastfeeding

 -  Irregular menses

 -  Standard MRI exclusion criteria