Study of Time-restricted Eating on Weight Loss.

Study Overview
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Brief Summary
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This is a randomized controlled trial studying the effects of time-restricted eating (TRE) on weight loss in obese humans. Obesity is the number one risk factor for type 2 Diabetes Mellitus (T2DM), and numerous studies demonstrate that weight loss is an effective strategy to prevent T2DM and improve the metabolic health of people diagnosed with T2DM. Unfortunately, classical calorie restriction diets often fail to produce long-term weight loss due to low compliance, reduced resting metabolic rate (RMR), and other factors. Therefore, novel dieting techniques must be explored in order to successfully treat obesity and prevent T2DM. Studies in mice provide compelling evidence that feeding/fasting cycles can be altered to produce beneficial effects on weight loss and metabolic health markers in the absence of calorie restriction. Limited research in human subjects suggests that this feeding paradigm may translate to human health as well, however, more research needs to be done in order to confirm this hypothesis. This study will determine if TRE can lead to weight loss in obese human subjects. Secondary outcomes include changes in body composition, HOMA-IR, hormonal and biochemical serum markers, RMR, and total energy expenditure (TEE).

Official Title
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Study of Time-restricted Eating on Weight Loss. A Randomized Controlled Trial of the Effects of Time-restricted Eating on Weight Loss in Obese Subjects.

Conditions
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Obesity, Insulin Resistance

Intervention / Treatment
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* Behavioral: Time-restricted Eating plan
* Behavioral: Consistent Meal timing plan


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BMI between 30-40 kg/m2 Participants must regularly consume breakfast (at least 5 days per week) Must speak, read, and comprehend English Access to reliable internet and/or wifi Must have a valid email address and phone number Must have a cellular phone with data plan Exclusion Criteria: HIV or immunocompromised Current or past cancer diagnosis Pregnant, breastfeeding, or planned pregnancy in next 6 months Beginning or ending hormonal contraception in next 6 months Current diagnosis of type or type 2 diabetes Currently taking glucose-lowering drugs, statins, or oral steroids History of gastric bypass surgery or any other weight-loss surgery History of anorexia or bulimia Frequent travel across time zones or unusual work hours Unable to fast for prolonged periods due to medical condition Unable to stand for several minutes without aid Cannot lie down on cushioned table for 30 minutes No internal metal artifacts that would alter body composition Unable to travel to UCSF for in-person testing Requires translator services

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 64 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: Parallel Assignment
Interventional Model Description: This is a randomized controlled trial. Participants will randomly assigned to one of two diet interventions for the duration of the 12-week study.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Time-restricted eating plan<br>Participants in this group will be instructed to fast every day from 8pm until 12pm the following day. From 12pm until 8pm, participants can eat and drink whatever they want. During fasting hours, participants can drink water and black coffee. | Behavioral: Time-restricted Eating plan<br>* Research team will prescribe an eating plan for the participant to follow for the 12 week study. The eating plan will consist of eating during a specified 8 hour window and fasting for the remaining 16 hours of the day.<br>|
| Active Comparator: Consistent Meal Timing Plan<br>Participants in this group will be instructed to eat three daily meals during specified eating times. Their first meal will be between 7am-11am. Second meal between 11am and 3pm, and third meal between 4pm-10pm. Participants will be encouraged to eat small snacks if needed so that they can eat their next meal during the specified window. | Behavioral: Consistent Meal timing plan<br>* Research team will prescribe an eating plan for the participant to follow for the 12 week study.The eating plan will consist of eating three structured meals each day during three specified meal windows.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weight Loss | Measure changes in weight during the 12 week study | Daily for 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fat loss | Measure changes in fat mass during the 12 week study using DXA data | Measured twice: Once at study start and once 12 weeks later | 
| Changes in lean mass | Measure changes in lean mass during the 12 week study using DXA data | Measured twice: Once at study start and once 12 weeks later | 
| Fasting insulin levels | Measure fasting insulin levels pre and post intervention | Measured twice: Once at study start and once 12 weeks later | 
| Resting metabolic rate | Will measure participants resting metabolic rate | Measured twice: Once at study start and once 12 weeks later | 
| Total energy expenditure | Will measure participants total energy expenditure during the week leading up to the study start and during the final week of the study | Measured twice: Once at study start and once 12 weeks later | 
| Changes in fasting glucose levels | WIll measure fasting blood glucose levels prior to diet intervention and again at study completion | Measured twice: Once at study start and once 12 weeks later | 
| Changes in HbA1c levels | WIll measure HbA1c levels prior to diet intervention and again at study completion | Measured twice: Once at study start and once 12 weeks later | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Weight loss, Diet, Time-restricted feeding