Effects of Periodic Fasting Versus Daily Energy Restriction on Metabolic Health

Study Overview
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Brief Summary
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The aim of this study is to examine whether periodic fasting improves markers of diabetes risk and cardiovascular health, and will compare this to the effects observed with daily dieting by energy restriction, and also with no change in energy intake. It is hypothesized that periodic fasting, with or without weight loss, will be as effective as daily energy restriction to improve markers of metabolic health and energy metabolism.

Official Title
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Effects of Periodic Fasting Versus Daily Energy Restriction on Metabolic Health

Conditions
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Insulin Resistance

Intervention / Treatment
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* Other: Periodic fasting
* Other: Energy restriction
* Other: Energy balance diet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Body mass index (BMI) between 25 and 42 kg/m2 weight stable (<5% fluctuation in body weight for the 6 months prior to study entry) Exclusion Criteria: history of cardiovascular disease, diabetes, major psychiatric disorders, and eating disorders use of prescribed or non-prescribed medications with may affect energy metabolism, gastrointestinal function, body weight, or appetite recent weight changes in 3 months prior to study entry uncontrolled asthma, current fever, upper respiratory infections individuals who regularly perform high intensity exercise (>2 sessions per week) pregnancy, lactation (breast feeding), women who are planning to become pregnant current intake of >140g of alcohol per week current smoker of cigarettes/cigars/marijuana current intake of any illicit substance experience claustrophobia in confined spaces has donated blood within the past 3 months unable to comprehend the study protocol experiences migraines

Ages Eligible for Study
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Minimum Age: 35 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Daily energy restriction<br>25% reduction in daily energy intake | Other: Energy restriction<br> <br> |
| Active Comparator: Energy balance diet<br>Diet provides 100% of energy requirements and is designed to achieve weight stability | Other: Energy balance diet<br> <br> |
| Experimental: Periodic fasting with weight loss<br>Fast 3 days per week, and consume 1.5 times usual amount of food on other days | Other: Periodic fasting<br> <br> Other: Energy restriction<br> <br> |
| Experimental: Periodic fasting without weight loss<br>Fast 3 days per week, and consume double usual amount of food on other days | Other: Periodic fasting<br> <br> Other: Energy balance diet<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Insulin sensitivity | assessed by hyperinsulinemic euglycemic clamp | 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma hormones and adipokines |  | 8 weeks | 
| Cognitive function, hunger, and mood |  | 8 weeks | 
| Oxidative stress, stress resistance, and lipid metabolism |  | 8 weeks | 
| Energy expenditure | resting energy expenditure, and total daily energy expenditure | 8 weeks |