Intermittent Fasting for the Treatment of Type 2 Diabetes Mellitus

Study Overview
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Brief Summary
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To test whether a lifestyle program featuring one of two forms of intermittent fasting (IER or TRE) can feasibly and effectively improve glycemia in patients with type 2 diabetes, and potentially induce diabetes remission.

Detailed Description
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Intermittent energy restriction (IER) and time-restricted eating (TRE) are two distinct forms of intermittent fasting which have yet to be compared for the treatment of type 2 diabetes. Investigators will test whether a comprehensive, intensive lifestyle program featuring each of these intermittent fasting approaches is feasible and effective for improving glycemic control in patients diagnosed with type 2 diabetes within the past 10 years. Both interventions will be delivered over one year in three phases: (1) a 12-week weight loss program featuring weekly group meetings, (2) a 12-week weight maintenance program featuring biweekly group meetings, and (3) a 6-month low-contact follow up period featuring monthly check-ins.

Official Title
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Intermittent Fasting for the Treatment of Type 2 Diabetes Mellitus

Conditions
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Type 2 Diabetes

Intervention / Treatment
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* Behavioral: Intermittent energy restriction (IER)
* Behavioral: Time Restricted Eating (TRE)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosed with type 2 diabetes in the past 10 years. Age 21-65 years BMI of 25 - 45 kg/m2 HbA1c of 6.7-9.5%, or those with A1c of <6.7% on glucose-lowering medications Ability to participate in a graduated physical activity program Clearance from study physician. Exclusion Criteria: Inability to attend health education meetings. Weight change of >=5% in the previous 3 months. Addition of new antihyperglycemic or weight-reducing medication in the previous 2 months. Serious medical risk such as ongoing treatment for cancer, uncontrolled hypertension, recent cardiac event, or other medical condition presenting acute risk of participation in a lifestyle change program. Untreated depression or anxiety, or increase in associated medications in the previous 3 months. Current participation in another lifestyle change intervention, such as a tobacco cessation program or physical activity program. Pregnancy or lactation within the previous six months Weight of >450 lbs Currently taking medications that may result in hypoglycemia during fasting and unwilling to stop prior to the study

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intermittent energy restriction (IER)<br>Intermittent fasting using a very-low energy diet (VLED; 550-800 kcal/d) 2-3 days per week | Behavioral: Intermittent energy restriction (IER)<br>* During Phase 1 (Weight Loss), participants will follow a very-low energy diet (VLED; 550-800 kcal/d) 2-3 days per week. On other days, participants do not have a specific kcal goal (non-fasting days). After Phase 1, IER participants will be instructed to follow a VLED 1-2 days per week as needed for weight maintenance.<br>|
| Experimental: Time-restricted eating (TRE)<br>Intermittent fasting using an 8-hour eating period. | Behavioral: Time Restricted Eating (TRE)<br>* Participants will eat within an 8-hour period most days (at least 5 days per week). All foods and beverages containing calories will be restricted to this 8-hour period but calorie-free beverages (coffee, tea, diet soda, etc.) are allowed at any time. TRE participants will follow healthy eating guidelines for weight loss during Phase 1 but not follow a specific kcal prescription or restrict intake thereafter.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Retention | Feasibility of IER and TRE over one year assessed by retention (# completed / # enrolled) and attendance (# classes attended / # classes offered). | 52 weeks | 
| Adherence to diet protocols | Acceptability of IER and TRE over one year as assessed by compliance to program recommendations (# weeks adhered / # study weeks). | Weekly from baseline to 52 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| HbA1c | Estimate the effects for both IER and TRE on long-term glycemic control assessed via HbA1c | Change from baseline to 24 weeks | 
| Oral Glucose Tolerance Test | Estimate the effects for both IER and TRE on fasting and 3 hr glucose result. | Change from baseline to 24 weeks | 
| Isulin resistance | Estimate the effects for both IER and TRE on insulin resistance estimated by the oral minimal model during a mixed meal tolerance test | Change from baseline to 24 weeks | 
| Insulin sensitivity | Estimate the effects for both IER and TRE on insulin sensitivity estimated by the oral minimal model during a mixed meal tolerance test | Change from baseline to 24 weeks |