Dinner Time 2: Effect of Delayed Eating or Sleeping on Metabolism (DT2)

February 2, 2026 updated by: Johns Hopkins University
This study examines the acute impact of eating an "early" versus "late" dinner. "Early" and "late" will be customized to individuals based on the individuals' own circadian rhythms. Healthy adults will have the adults' circadian rhythm assessed by measuring the adults' dim light melatonin onset (DLMO). Based on the timing of DLMO, participants will be randomized to eating dinner before DLMO or after DLMO. The investigators will also compare the effects of delaying sleep relative to dinner time. Participants will eat meals in the laboratory and have serial plasma samples collected to examine profiles of free fatty acids, glucose, insulin, triglycerides, and oxidation of dietary fat.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Obesity is a worldwide health problem. Recent studies suggest that the timing of meals may be critically important for weight control and cardiovascular health. Consuming calories later in the day is associated with greater risks of obesity, metabolic syndrome, and cardiovascular disease. Interventional diet studies also show more effective weight loss with early, rather than later eating. The investigators conducted a randomized crossover study comparing the metabolic effect of a "routine" dinner (RD,18:00) with that of an isocaloric "late" dinner (LD, 22:00) in 20 healthy volunteers. The investigators recently published results of this study, which the investigators now refer to as "Dinner Time 1". Relative to RD, LD increased post-dinner glucose peak by ~18% and lowered palmitate oxidation by ~10%. However, it is still unclear whether LD-induced impaired metabolic dysfunction is caused by eating at the "wrong" time relative to the body's central circadian clock, or it is caused by eating too close to bedtime, when sleep reduces metabolic demands.

To address this question, the investigators are now enlarging the scope of the present study, which the investigators now refer to as "Dinner Time 2". In Dinner Time 2, the investigators will examine the impacts of early dinner, late dinner, and the impact of delaying sleep after late dinner. The investigators will compare (1) the impact of early dinner time with later dinner time relative to DLMO with a routine sleep time; and (2) the impact of routine bedtime with late bedtime with a fixed late dinner time.

The investigators will examine the nocturnal and next-morning metabolic profile in a 3-arm randomized crossover study of healthy volunteers:

Arm 1: Early Dinner (dinner at DLMO-3, sleep at DLMO+2) Arm 2: Late Dinner (dinner at DLMO+1, sleep at DLMO+2) Arm 3: Late Dinner/Late Sleep (dinner at DLMO+1, sleep at DLMO+6)

The investigators will use serial blood sampling to assess the metabolic response to meals, and use an ingested stable isotope [(2H31)palmitate] tracer to calculate the oxidation of dietary lipid eaten at the different times.

Study Type

Interventional

Enrollment (Actual)

41

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Maryland
      • Baltimore, Maryland, United States, 21224
        • Johns Hopkins Bayview Medical Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 30 years (Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion:

  • Healthy male and female adult volunteers, age 18-30
  • BMI 18-30 kg/m2
  • Accustomed to a bedtime before 1:00 A.M. or having mid-sleep on free days (MSF) earlier than 5 A.M. from the Munich Chronotype Questionnaire (MCTQ) (to exclude extreme late chronotypes)

Exclusions:

  • Sleep disorder including insomnia, sleep apnea, circadian rhythm disorder, restless leg syndrome, narcolepsy, shift work sleep disorder
  • Gastroesophageal reflux disease that affects ability to tolerate a dinner close to bed time.
  • Chronic use of sedative hypnotics, anxiolytics, opiates
  • Use of medications that can affect circadian rhythm (beta blockers, melatonin)
  • Active smoking (may interfere with metabolism and Clinical Research Unit (CRU) activities)
  • Diabetes (type 1 or 2)
  • HbA1c point of care >= 6.5%
  • Kidney disease
  • Any known history of an inherited metabolic disorder
  • Pregnant or lactating female (pregnancy test will be required)
  • Professional or collegiate athlete
  • Travel across >1 time zone within a 3-month period before and during the protocol
  • DLMO > 24:00 will be excluded from the metabolic study visits

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Early Dinner first
Participants will be served dinner and a stable isotope of palmitate to measure fat oxidation, at an early dinner time (DLMO-3h) followed by a sleep study (DLMO+2h). This arm will cross-over to the other 2 arms in random order.
Behavioral: Early dinner
Dinner at DLMO-3, sleep at DLMO+2
Behavioral: Late Dinner
Dinner at DLMO+1, sleep at DLMO+2
Behavioral: Late Dinner + Late Sleep
Dinner at DLMO+1, sleep at DLMO+6
Experimental: Late Dinner first
Participants will be served dinner and a stable isotope of palmitate to measure fat oxidation, at a late dinner time (DLMO+1h) followed by a sleep study (DLMO+2h). This arm will cross-over to the other 2 arms in random order.
Behavioral: Early dinner
Dinner at DLMO-3, sleep at DLMO+2
Behavioral: Late Dinner
Dinner at DLMO+1, sleep at DLMO+2
Behavioral: Late Dinner + Late Sleep
Dinner at DLMO+1, sleep at DLMO+6
Experimental: Late Dinner + Late Sleep first
Participants will be served dinner and a stable isotope of palmitate to measure fat oxidation, at a late dinner time (DLMO+1h) followed by delayed bedtime (DLMO+6h). This arm will cross-over to the other 2 arms in random order.
Behavioral: Early dinner
Dinner at DLMO-3, sleep at DLMO+2
Behavioral: Late Dinner
Dinner at DLMO+1, sleep at DLMO+2
Behavioral: Late Dinner + Late Sleep
Dinner at DLMO+1, sleep at DLMO+6

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in Glucose (mg/dl)
Time Frame: Baseline, 4 weeks and 8 weeks
Serial blood samples taken during visit, 25 samples taken over 25 hours (One every hour) per visit.
Baseline, 4 weeks and 8 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in Free Fatty Acids (FFA, mmol/L)
Time Frame: Baseline, 4 weeks and 8 weeks
Serial blood samples taken during visit, 25 samples taken over 25 hours (One every hour) per visit.
Baseline, 4 weeks and 8 weeks
Change in Insulin (mcU/ml)
Time Frame: Baseline, 4 weeks and 8 weeks
Serial blood samples taken during visit, 25 samples taken over 25 hours (One every hour) per visit.
Baseline, 4 weeks and 8 weeks
Change in Triglycerides (mg/dl)
Time Frame: Baseline, 4 weeks and 8 weeks
Serial blood samples taken during visit, 25 samples taken over 25 hours (One every hour) per visit.
Baseline, 4 weeks and 8 weeks
Change in Oxidation of palmitate (percent of isotope enrichment)
Time Frame: Baseline, 4 weeks and 8 weeks
Serial blood samples taken during visit (14 samples per visit).
Baseline, 4 weeks and 8 weeks
Change in melatonin [Dim light melatonin onset (DLMO)]
Time Frame: At 2 weeks prior to baseline (samples drawn every 30 minutes, up to 7 hours)
Serial saliva samples taken during visit, 14 samples taken over 7 hours (one sample every 30 minutes) to access change in melatonin levels (pg/ml) over 7 hours.
At 2 weeks prior to baseline (samples drawn every 30 minutes, up to 7 hours)
Sleep architecture
Time Frame: Baseline, 4 weeks and 8 weeks
Sleep stage distribution by EEG during each of the 3 sleep studies.
Baseline, 4 weeks and 8 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Johns Hopkins University

Collaborators

University of Arkansas
National Marrow Donor Program

Investigators

  • Principal Investigator: Jonathan Jun, MD, Johns Hopkins University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 15, 2021

Primary Completion (Actual)

June 19, 2025

Study Completion (Actual)

June 19, 2025

Study Registration Dates

First Submitted

December 11, 2020

First Submitted That Met QC Criteria

December 11, 2020

First Posted (Actual)

December 17, 2020

Study Record Updates

Last Update Posted (Actual)

February 4, 2026

Last Update Submitted That Met QC Criteria

February 2, 2026

Last Verified

February 1, 2026

More Information

Terms related to this study

Keywords

Other Study ID Numbers

  • IRB00156120-2

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

We will provide raw data (without identifying information) to journals or other researchers upon request.

IPD Sharing Time Frame

The data will be provided upon request within 1 year after publication and will be available to indefinitely.

IPD Sharing Access Criteria

The PI will accept requests from other researchers who are examining pertinent outcomes.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • SAP
  • ICF

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Healthy

Clinical Trials on Early dinner

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Costa Rica

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe