The Effect of Time-Restricted Eating in Cardiometabolic Health

Study Overview
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Brief Summary
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Time-restricted eating (TRE) is a dietary manipulation that involves restricting food intake to 6-12 h/day with no energy intake the rest of the day. In rodents, TRE improves metabolic function without caloric restriction, potentially by activating nutrient sensing mechanisms and effects on circadian oscillations. However, an understanding of the effect of TRE on cardiometabolic health in people is not clear and few studies have evaluated this issue. Accordingly, the investigators propose to conduct a randomized controlled trial in people with obesity and prediabetes to determine the effect of 9 h TRE for 12 weeks, without a change in body weight, on key metabolic outcomes that are risk factors for cardiovascular disease (CVD): 1) multi-organ insulin sensitivity; 2) 24 h metabolic homeostasis and diurnal rhythm; and 3) adipose tissue and skeletal muscle biology. The proposed studies will elucidate the cardiometabolic implications of TRE in people with obesity and prediabetes.

Official Title
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The Effect of Time-Restricted Eating in Cardiometabolic Health

Conditions
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Obesity, Pre-diabetes

Intervention / Treatment
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* Other: 9 hours daily eating window
* Other: 15 hours daily eating window


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: body mass index 30-39.9 kg/m2 fasting plasma glucose 100-125 mg/dl, or 2h OGTT plasma glucose 140-199 mg/dl or hemoglobin A1C 5.7-6.4% self-reported habitual eating period > 15 h per day Exclusion Criteria: shift worker, recent or expected travel crossing time zones fasting >12 h/day more than once a week or vegan shift worker, recent or expected travel crossing time zones fasting >12 h/day more than once a week or vegan > once a week no food intake after 1800 h habitually waking up before 0400 h and sleeping before 2230 h ≥ 150 min per week of structured exercise unstable weight (>5% change the last 2 months) type 2 diabetes or other major chronic disease sleep disorder cancer in last 5 years conditions that render subject unable to complete all testing procedures use of medications that affect the study outcome measures or increase the risk of study procedures and that cannot be temporarily discontinued (e.g., steroids, alpha or beta adrenergic blockers or agonists, etc.) smoking and illegal drug use pregnant or lactating menopause individuals that have performed procedures involving substantial exposure to radiation in the last 12 months gastrointestinal or bariatric surgery unable to grant voluntary informed consent or comply with the study instructions individuals who are not yet adults (infants, children, teenagers) prisoners

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 70 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Participants will be randomly assigned to one of two diet interventions: TRE group (eating all their food for the day in 9 hours) or the control group (eating all their food for the day in 15 hours) for 12 weeks. Tests to asses changes in metabolism will be performed before and after the intervention.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: TRE group<br>Time-restricted eating group | Other: 9 hours daily eating window<br>* Participants assigned to the TRE group will have to consume all their daily meals and snacks during a 9-hour window for 12 weeks.<br>|
| Other: Control group<br>Time-unrestricted eating group | Other: 15 hours daily eating window<br>* Participants assigned to the control group will have to consume all their daily meals and snacks during a 15-hour window for 12 weeks.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Insulin sensitivity | Insulin sensitivity will be assessed by using a hyperinsulinemic euglycemic clamp procedure in conjunction with infusion of stable isotope tracers. | 3 months (pre-post intervention) | 
| 24 h glycemic control | Changes in plasma glucose concentration will be assessed during a 24 h feeding study. | 3 months (pre-post intervention) | 
| Adipose tissue gene expression | Changes in the expression of genes involved in energy metabolism will be assessed by using qPCR. | 3 months (pre-post intervention) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peripheral diurnal rhythmicity in in peripheral mononuclear blood cells | We will evaluate changes in clock gene expression | 3 months (pre-post intervention) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Chrono-nutrition, Adipose tissue, Skeletal muscle, Insulin sensitivity, Diurnal rhythm