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Comparison of Time-Restricted Feeding Versus Grazing (TIMED EATING)

Primary Purpose

Prediabetes, Insulin Resistance, Vascular Diseases

Status
Completed
Phase
Not Applicable
Locations
United States
Study Type
Interventional
Intervention
Time-Restricted Feeding
Grazing
Sponsored by
Pennington Biomedical Research Center
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional prevention trial for Prediabetes focused on measuring Time-restricted feeding, Intermittent fasting, Prediabetes, Insulin resistance, Glucose tolerance, Insulin sensitivity, Circadian rhythms, Diurnal

Eligibility Criteria

35 Years - 70 Years (Adult, Older Adult)MaleAccepts Healthy Volunteers

Inclusion Criteria:

  • Are male
  • Overweight: Have a body mass index between 25 and 50 kg/m^2 inclusive (a number calculated from height and weight)
  • Are 35-70 years of age
  • Have a hemoglobin A1C between 5.5 - 6.4% or prior medical indication of prediabetes
  • Have a blood sugar level between 140 and 199 mg/dL two hours after drinking a sugary solution (OGTT)
  • Have been eating dinner at least 8.5 hours after eating breakfast at least 90% of the time during the past year
  • Have not fasted (go for a day without any food) more than 12 days total during the past year
  • Be willing to eat most meals at Pennington Biomedical and/or under supervision
  • Not eat any food other than that served by Pennington Biomedical
  • Not drink any alcohol, juice, or other beverages that have calories other than what is served by Pennington Biomedical
  • Keep water and no-calorie drinks like tea or diet soda the same during both of the timed eating periods
  • Be willing to eat your meals according to the fixed schedules

Exclusion Criteria:

  • Have diabetes or are on anti-diabetes medication
  • Have evidence of cardiovascular disease
  • Suffer from significant cardiovascular, renal (kidney), cardiac (heart), liver, lung or nervous system disease
  • Evidence of significant gastrointestinal issues or surgery that impacts nutrient absorption
  • Regularly use medications such as steroids, beta blockers, and adrenergic-stimulating agents
  • Are on any regular medicine that has not had the same dose for 1 month or longer
  • Have a clinically significant abnormality as measured by a blood test
  • Regularly drink alcohol (more than 2 servings per day)
  • Have to do any kind of heavy physical activity
  • Currently perform overnight shift work more than one day a week
  • Are not able to eat only the food served to you by Pennington Biomedical, while in the study
  • Are not able to stop drinking alcohol or other drinks with calories (e.g., soda, juice) other than what is served to you by Pennington Biomedical, while in the study

Sites / Locations

  • Pennington Biomedical Research Center

Arms of the Study

Arm 1

Arm 2

Arm Type

Experimental

Placebo Comparator

Arm Label

Time-Restricted Feeding (early in the day eating)

Grazing

Arm Description

Participants will consume all meals early in the day and within a 6-hour window.

Participants will eat meals spread out over the course of the day.

Outcomes

Primary Outcome Measures

Change in Glucose Tolerance
Glucose tolerance and indices of glucose homeostasis will be determined using an Oral Glucose Tolerance Test (OGTT).

Secondary Outcome Measures

Change in Vascular Function
Macro- and micro-vascular function will be assessed by Radial Artery Applanation Tonometry and by Orthogonal Polarization Spectroscopy. The endpoints measured by these two tests include aortic blood pressure, arterial stiffness, capillary density, and red blood cell velocity.
Change in Inflammation and Metabolic Markers
Serum markers of inflammation, such as C-Reactive Protein (CRP) and inflammatory cytokines, and of metabolic processes will be measured (composite measure).

Full Information

First Posted
July 3, 2013
Last Updated
March 15, 2018
Sponsor
Pennington Biomedical Research Center
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1. Study Identification

Unique Protocol Identification Number
NCT01895179
Brief Title
Comparison of Time-Restricted Feeding Versus Grazing
Acronym
TIMED EATING
Official Title
Time-Restricted Feeding to Improve Glucose Tolerance and Vascular Condition
Study Type
Interventional

2. Study Status

Record Verification Date
March 2018
Overall Recruitment Status
Completed
Study Start Date
July 2013 (undefined)
Primary Completion Date
November 2017 (Actual)
Study Completion Date
November 2017 (Actual)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Principal Investigator
Name of the Sponsor
Pennington Biomedical Research Center

4. Oversight

5. Study Description

Brief Summary
The purpose of this pilot study is to find out what eating meals in a short time period early in the day (time-restricted feeding) versus eating meals spread out during the day (grazing) does to the body's ability to control blood sugar and to the health of its blood vessels. The investigators hypothesize that time-restricted feeding will be more effective at improving glucose tolerance and vascular condition (inflammation and micro- and macro-vascular function) than grazing.
Detailed Description
Each participant will eat according to one of the two eating schedules (grazing or time-restricted feeding) for 5 weeks, have a 7-week washout period, and then eat according to the other eating schedule for 5 weeks. Measurements of glucose homeostasis and vascular condition will be performed before and after a participant follows each eating schedule.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Prediabetes, Insulin Resistance, Vascular Diseases
Keywords
Time-restricted feeding, Intermittent fasting, Prediabetes, Insulin resistance, Glucose tolerance, Insulin sensitivity, Circadian rhythms, Diurnal

7. Study Design

Primary Purpose
Prevention
Study Phase
Not Applicable
Interventional Study Model
Crossover Assignment
Masking
None (Open Label)
Allocation
Randomized
Enrollment
8 (Actual)

8. Arms, Groups, and Interventions

Arm Title
Time-Restricted Feeding (early in the day eating)
Arm Type
Experimental
Arm Description
Participants will consume all meals early in the day and within a 6-hour window.
Arm Title
Grazing
Arm Type
Placebo Comparator
Arm Description
Participants will eat meals spread out over the course of the day.
Intervention Type
Other
Intervention Name(s)
Time-Restricted Feeding
Intervention Description
Time-restricted feeding is a variant of intermittent fasting that involves eating all of one's calories within a few hours each day (typically 4-9 hours), followed by a daily fast of 15-20 hours.
Intervention Type
Other
Intervention Name(s)
Grazing
Intervention Description
Grazing involves eating meals spread out over the course of the day.
Primary Outcome Measure Information:
Title
Change in Glucose Tolerance
Description
Glucose tolerance and indices of glucose homeostasis will be determined using an Oral Glucose Tolerance Test (OGTT).
Time Frame
Before and after 5 weeks on each feeding schedule
Secondary Outcome Measure Information:
Title
Change in Vascular Function
Description
Macro- and micro-vascular function will be assessed by Radial Artery Applanation Tonometry and by Orthogonal Polarization Spectroscopy. The endpoints measured by these two tests include aortic blood pressure, arterial stiffness, capillary density, and red blood cell velocity.
Time Frame
Before and after 5 weeks on each feeding schedule
Title
Change in Inflammation and Metabolic Markers
Description
Serum markers of inflammation, such as C-Reactive Protein (CRP) and inflammatory cytokines, and of metabolic processes will be measured (composite measure).
Time Frame
Before and after 5 weeks on each feeding schedule

10. Eligibility

Sex
Male
Minimum Age & Unit of Time
35 Years
Maximum Age & Unit of Time
70 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion Criteria: Are male Overweight: Have a body mass index between 25 and 50 kg/m^2 inclusive (a number calculated from height and weight) Are 35-70 years of age Have a hemoglobin A1C between 5.5 - 6.4% or prior medical indication of prediabetes Have a blood sugar level between 140 and 199 mg/dL two hours after drinking a sugary solution (OGTT) Have been eating dinner at least 8.5 hours after eating breakfast at least 90% of the time during the past year Have not fasted (go for a day without any food) more than 12 days total during the past year Be willing to eat most meals at Pennington Biomedical and/or under supervision Not eat any food other than that served by Pennington Biomedical Not drink any alcohol, juice, or other beverages that have calories other than what is served by Pennington Biomedical Keep water and no-calorie drinks like tea or diet soda the same during both of the timed eating periods Be willing to eat your meals according to the fixed schedules Exclusion Criteria: Have diabetes or are on anti-diabetes medication Have evidence of cardiovascular disease Suffer from significant cardiovascular, renal (kidney), cardiac (heart), liver, lung or nervous system disease Evidence of significant gastrointestinal issues or surgery that impacts nutrient absorption Regularly use medications such as steroids, beta blockers, and adrenergic-stimulating agents Are on any regular medicine that has not had the same dose for 1 month or longer Have a clinically significant abnormality as measured by a blood test Regularly drink alcohol (more than 2 servings per day) Have to do any kind of heavy physical activity Currently perform overnight shift work more than one day a week Are not able to eat only the food served to you by Pennington Biomedical, while in the study Are not able to stop drinking alcohol or other drinks with calories (e.g., soda, juice) other than what is served to you by Pennington Biomedical, while in the study
Facility Information:
Facility Name
Pennington Biomedical Research Center
City
Baton Rouge
State/Province
Louisiana
ZIP/Postal Code
70808
Country
United States

12. IPD Sharing Statement

Citations:
PubMed Identifier
33512717
Citation
Allaf M, Elghazaly H, Mohamed OG, Fareen MFK, Zaman S, Salmasi AM, Tsilidis K, Dehghan A. Intermittent fasting for the prevention of cardiovascular disease. Cochrane Database Syst Rev. 2021 Jan 29;1(1):CD013496. doi: 10.1002/14651858.CD013496.pub2.
Results Reference
derived

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Comparison of Time-Restricted Feeding Versus Grazing

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