Meal Timing and Blood Pressure

Study Overview
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Brief Summary
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Brain blood flow, blood pressure, and neurovascular control mechanisms will be measured in middle-aged adults before and after a brief intervention period. The intervention will consist of changing the time in which the participant consumes food each day.

Detailed Description
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Healthy adults experience a 10-20% decrease in night-time blood pressure, compared with day-time blood pressure. However, 20-40% of middle-aged adults do not demonstrate a decrease in blood pressure. Abnormal blood pressure patterns are linked to sleep disturbances, hypertension, and associated with elevated cardiovascular risk and mortality. Additionally, abnormal diurnal blood pressure patterns are associated with impaired neurovascular control of the circulation, contributing to an increased risk of hypertension, stroke, and cardiovascular disease. Importantly, midlife is the critical period for implementing interventions to prevent or delay future cardiovascular disease. Recent data demonstrates that time-restricted feeding may normalize blood pressure patterns. The overall goal of this study is to determine if time-restricted feeding normalizes blood pressure patterns and improves neurovascular control. The research aims are: To determine the effect of meal timing on blood pressure patterns in middle-aged adults. To determine the effect of meal timing on neurovascular control in middle-aged adults.

Official Title
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The Impact of Meal Timing on Neurovascular Control in Adults

Conditions
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Blood Pressure, Neurovascular Control

Intervention / Treatment
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* Behavioral: Time-Restricted Feeding


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BMI ≤ 34 kg/m2 Non-smoking Sedentary or recreationally active ≤ 2 Alcoholic drinks per day Female subjects: Perimenopausal/Postmenopausal Exclusion Criteria: History or evidence of hepatic, renal, hematological, peripheral vascular disease, or stroke/neurovascular disease, diabetes, uncontrolled hypertension, sleep apnea On medications used to treat/manage diseases listed above Work overnight shifts Clinically diagnosed anxiety or depression Pregnant or trying to become pregnant Significant surgical history Other significant medical conditions at investigator's discretion

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 65 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: Basic Science
Intervention Model: Single Group Assignment
Interventional Model Description: The interventional study model used will consist of a time-restricted feeding intervention.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Time-Restricted Feeding<br>Control (Baseline): Blood pressure and neurovascular control will be measured. Post-Intervention: Blood pressure and neurovascular control will be measured. | Behavioral: Time-Restricted Feeding<br>* After baseline measurements have been completed, participants will enroll in a time-restricted feeding intervention. Participants will be asked to restrict the time in which they eat each day to 10 hours, fasting for the remaining 14 hours. Participants will also be asked to finish their last meal of the day at least 2 hours prior to bedtime.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood Pressure measured continuously over a period of 24 hour | Utilize an ambulatory blood pressure monitor to measure blood pressure values continuously over a 24-hour period. | Continuously over a 24-hour period | 
| Neurovascular Control: Change in the brain blood flow | Change in brain blood flow will be measured using a transcranial Doppler ultrasound in response to a breathing test. | Baseline and 5 weeks | 
| Neurovascular Control: Change in the blood pressure | Change in blood pressure in response to a breathing test. | Baseline and 5 weeks | 
| Neurovascular Control: change in the sympathetic nerve activity | Change in sympathetic nerve activity will be measured using microneurography in response to a breathing test. | Baseline and 5 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Meal Timing, Blood Pressure, Time-Restricted Feeding, Sympathetic Nerve Activity