Daytime vs. Delayed Eating Among Obese Individuals

NCT03354169 | Completed Results DMC

• 2 other identifiers: 828317R01DK117488
• Study Type: interventional
• Target: 38
• Locations: 1 country
• Sites: 1

Brief Summary

The randomized, cross-over design study is designed to determine how timing of eating affects weight, adiposity, energy metabolism, and gene expression. Obese participants will be provided isocaloric meals and snacks to be consumed in one of two prescribed eating conditions -- daytime eating and delayed eating.

Conditions

Obesity

Keywords

Metabolism; Eating; Circadian Rhythms

Outcome Measures

Primary Outcomes (4)

• Body Mass (Weight)

  changes in body mass, as measured by a calibrated digital scale, will be explored.

  pre-post changes between the daytime and delayed eating conditions (each 8 weeks long)

• Adiposity - Total Body Fat

  changes in measures of total body fat, as measured by a DEXA scan, will be explored.

  pre-post changes between the daytime and delayed eating conditions (8 weeks).

• Energy Homeostasis Outcomes - REE

  Changes in resting energy expenditure values will be explored.

  pre-post changes between the daytime and delayed eating conditions (8 weeks).

• Energy Homeostasis - Respiratory Quotient

  Respiratory quotient (RQ) was measured with a Parvo-Medics metabolic cart. It is calculated from the ratio of carbon dioxide produced by the body to oxygen consumed by the body, when the body is in a steady state.

  pre-post changes between the daytime and delayed eating conditions (8 weeks).

Study Arms (3)

Daytime Eating Condition

EXPERIMENTAL

Participants will be asked to eat all of their meals and snacks, as provided by the study, between 0800 and 1900.

Behavioral: Eating Condition

Delayed Eating Condition

EXPERIMENTAL

Participants will be asked to eat all of their meals and snacks, as provided by the study, between 1200 and 2300.

Behavioral: Eating Condition

Withdrawn before randomization

OTHER

Two participants completed the screening process and started the first inpatient assessment visit but were withdrawn prior to completion of the assessment visit and were not randomized to start the intervention. They were not included in data analysis.

Other: No Intervention; withdrawn before randomization

Interventions

Eating Condition BEHAVIORAL

Participants will be randomly assigned to eat per the prescribed eating condition for 8 weeks during eating condition 1. They will complete the alternate eating condition for 8 weeks during eating condition 2.

Daytime Eating Condition; Delayed Eating Condition

No Intervention; withdrawn before randomization OTHER

These participants were withdrawn and did not receive an intervention.

Withdrawn before randomization

Eligibility Criteria

• Age: 21 Years - 50 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• age 21-50
• BMI of 30-50 kg/m2
• stable weight (±10 lb) over the previous 6 months
• women must be pre-menopausal with regular menstrual cycles

You may not qualify if:

• unstable, serious medical conditions
• use of medicine linked to weight gain/loss
• cardiac conditions
• cancer
• diabetes
• autoimmune disease
• use of illicit drugs, melatonin, diuretics or hypnotics
• involved in a current weight loss program
• presence of an untreated sleep disorder (determined by surveys and actigraphy)
• those who work shift work
• those with extreme chronotypes
• habitual waking outside of 0600h-0930h
• habitual bedtime \<2200h or \>2400h
• sleep duration of \<6.5 or \>8.5 h/night.
• structured exercise \>3 d/wk, for \>30 min measured by exercise logs and actigraphy; normal activity levels are required during the study (±30 min/wk of baseline level).

Sponsors & Collaborators

• University of Pennsylvania: lead
• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK): collaborator

Study Sites (1)

Center for Weight and Eating Disorders, Perelman School of Medicine, University of Pennsylvania

Philadelphia, Pennsylvania, 19104, United States

Location

MeSH Terms

Conditions

Obesity

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Results Point of Contact

• Title: Kelly C. Allison, PhD
• Organization: University of Pennsylvania

kca@pennmedicine.upenn.edu

215-898-2823

Study Officials

• Kelly Allison, PhD

  University of Pennsylvania

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Director, Center for Weight and Eating Disorders

Model Details: Randomized within subjects, cross-over design

Study Record Dates

• First Submitted: November 21, 2017
• First Posted: November 27, 2017
• Study Start: February 7, 2018
• Primary Completion: March 2, 2023
• Study Completion: March 2, 2023
• Last Updated: November 21, 2025
• Results First Posted: November 21, 2025

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)