The Effect of Time-restricted Feeding on Physiological Function in Middle-aged and Older Adults

Study Overview
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Brief Summary
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The purpose of this study is to assess the safety and efficacy of time-restricted feeding (eating within an 8-hour window) for improving physiological function (vascular, motor, cognitive and metabolic function) in healthy middle-aged and older adults.

Detailed Description
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Overall, the proposed research project has the long-term potential to influence clinical practice by establishing novel therapies for treating multiple domains of age-associated physiological dysfunction and thereby reducing the risk of clinical disease and disability.

Official Title
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The Effect of Time-restricted Feeding on Physiological Function in Middle-aged and Older Adults

Conditions
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Aging

Intervention / Treatment
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* Behavioral: Time Restricted Feeding


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ability to provide informed consent Baseline brachial flow-mediated dilation (FMD) < 6%Δ (rationale: non-invasive screening to ensure exclusion of subjects with exceptionally high baseline endothelial function. Ability to perform motor and cognitive tests (e.g., can rise from a chair, walk for 2 min, climb 10 stairs) Women will be confirmed as postmenopausal (either natural or surgical) based on cessation of menses for >1 year. Exclusion Criteria: Ages <55 years or ≥80 years Occupation that requires night-shift work or abnormal hours that would disrupt eating schedule Dietary habit of regularly skipping meals, already eating within a  10 hour window, or any other form of restrictive eating. Unable to adhere to an 8 hour eating window for the length of the study period Participation in regular vigorous aerobic/endurance exercise (>3 vigorous bouts/week) Not weight stable in the prior 3 months (>2 kg weight change). Body mass index (BMI) >40 kg/m^2 (rationale: vascular function measurements can be inaccurate in severely obese subjects) Current smoking Diagnosis of a chronic clinical disease (e.g., coronary artery/peripheral artery/cerebrovascular diseases, diabetes, chronic kidney disease requiring dialysis, neurological disorders or diseases that may affect motor/cognitive functions [multiple sclerosis, Parkinson's disease, polio, Alzheimer's disease, dementia or other brain diseases of aging]), except hypertension and hyperlipidemia. Having unstable angina, acute myocardial infarction, coronary angioplasty, or aorto- coronary bypass surgery as defined by the occurrence of an event, symptom, surgery, or change in medication and/or dosage within 3 months prior to enrollment. Having thyroid disease that is not controlled by medications or <3 month's use of a particular medication and/or dosage (rationale: uncontrolled thyroid diseases are associated with alterations in vascular function). Having past or present alcohol dependence or abuse, as defined by the American Psychiatry Association, Diagnostic and Statistical Manual of Mental Disorders

Ages Eligible for Study
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Minimum Age: 55 Years
Maximum Age: 79 Years

Sexes Eligible for Study
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All

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: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Normal Feeding<br>Subjects will be instructed to eat within their normal feeding window. | |
| Experimental: Time Restricted Feeding<br>Subjects will be instructed to eat with an 8 hour feeding window, starting between 10:30-11:30 AM and stopping between 5:30-6:30 PM. | Behavioral: Time Restricted Feeding<br>* consuming all daily calories within an 8 hour feeding window<br>* Other names: TRF;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Endothelium Dependent Dilation | Brachial Artery Flow-Mediated Dilation (FMD) | 6 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arterial Stiffness | Aortic Pulse Wave Velocity (PWV) | 6 weeks | 
| Cognitive Function | NIH Toolbox Cognitive Function Battery | 6 weeks | 
| Motor Function | NIH Toolbox Motor Function Battery | 6 weeks | 
| Metabolic Function | Oral glucose tolerance test (OGTT) | 6 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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time restricted feeding, endothelial function, arterial stiffness, intermittent fasting