ClinicalTrials.gg
CompletedNCT03393195TREATUpdated Mar 3, 2020

Study of Time-restricted Eating on Weight Loss.

An interventional study of Time-restricted Eating plan and Consistent Meal timing plan in Obesity and Insulin Resistance, sponsored by University of California, San Francisco. Completed at 1 site in United States. Open to participants aged 18 Years to 64 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2020-03-03.

Sponsored by University of California, San Francisco · Not applicable, Interventional, and Treatment

Phase
Not applicable
Study type
Interventional
Enrollment
137
Allocation
Randomized
Ages
18 Years to 64 Years
Sex
All
01

Study summary

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).

02

Conditions studied

  • Obesity
  • Insulin Resistance

Keywords

  • Weight loss
  • Diet
  • Time-restricted feeding
03

In context

Obesity

11,522 studies on the registry are indexed under Obesity; 2,033 are open to participants now.

This study's enrollment of 137 is above the median of 67 across 9,006 interventional studies indexed under Obesity.

Browse Obesity studies →

Lead sponsor

University of California, San Francisco is the lead sponsor of 2,169 studies on the registry; 372 are open to participants now.

Of its 267 completed or terminated interventional studies of FDA-regulated products, 202 (76%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 64 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • 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

Exclusion Criteria:

  • or
  • Current or past cancer diagnosis
  • Pregnant, breastfeeding, or planned pregnancy in next 6 months
  • Beginning or ending hormonal in next 6 months
  • Current diagnosis of type or type 2 diabetes
  • Currently taking glucose-lowering drugs, statins, or oral
  • 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
Terms in these criteria, in plain language(5)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

BMI (body mass index)

Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.

What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
137 participants (actual)

Study arms

  • Experimental
    Time-restricted eating plan

    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

  • Active comparator
    Consistent Meal Timing Plan

    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

Interventions

  • BehavioralTime-restricted Eating plan

    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.

  • BehavioralConsistent Meal timing plan

    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.

06

What researchers measure

Primary outcomes

  1. Weight Loss

    Measure changes in weight during the 12 week study

    Time frame: Daily for 12 weeks

Secondary outcomes

  1. Fat loss

    Measure changes in fat mass during the 12 week study using DXA data

    Time frame: Measured twice: Once at study start and once 12 weeks later

  2. Changes in lean mass

    Measure changes in lean mass during the 12 week study using DXA data

    Time frame: Measured twice: Once at study start and once 12 weeks later

  3. Fasting insulin levels

    Measure fasting insulin levels pre and post intervention

    Time frame: Measured twice: Once at study start and once 12 weeks later

  4. Resting metabolic rate

    Will measure participants resting metabolic rate

    Time frame: Measured twice: Once at study start and once 12 weeks later

  5. 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

    Time frame: Measured twice: Once at study start and once 12 weeks later

  6. Changes in fasting glucose levels

    WIll measure fasting blood glucose levels prior to diet intervention and again at study completion

    Time frame: Measured twice: Once at study start and once 12 weeks later

  7. Changes in HbA1c levels

    WIll measure HbA1c levels prior to diet intervention and again at study completion

    Time frame: Measured twice: Once at study start and once 12 weeks later

07

Study locations

1 site
  • UCSF Medical Center
    San Francisco, California 94143, United States
08

References and documents

Publications

  • Lowe DA, Wu N, Rohdin-Bibby L, Moore AH, Kelly N, Liu YE, Philip E, Vittinghoff E, Heymsfield SB, Olgin JE, Shepherd JA, Weiss EJ. Effects of Time-Restricted Eating on Weight Loss and Other Metabolic Parameters in Women and Men With Overweight and Obesity: The TREAT Randomized Clinical Trial. JAMA Intern Med. 2020 Nov 1;180(11):1491-1499. doi: 10.1001/jamainternmed.2020.4153. Erratum In: JAMA Intern Med. 2020 Nov 1;180(11):1555. doi: 10.1001/jamainternmed.2020.6728. JAMA Intern Med. 2021 Jun 1;181(6):883. doi: 10.1001/jamainternmed.2020.8941. PubMed 32986097 ↗

Study documents

PDFs hosted by the registry, ClinicalTrials.gov.

Individual participant data

Plan to share: No

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Mar 3, 2020, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT03393195
Responsible party
Sponsor
First posted
Jan 8, 2018
Start date
Jul 30, 2018
Primary completion
Oct 23, 2019
Completion
Jan 10, 2020
Last update
Mar 3, 2020

Study contacts

Ethan J Weiss, MD
principal investigator · University of California, San Francisco

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Feb 2020. You cannot join it, but the record below documents what was studied.

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