NCT04743271

Brief Summary

The goals of this study are to uncover the influence of diet on the human circadian timing system. The protocol is a 46-day (28 outpatient days, 18 inpatient days over two 9 day visits) randomized cross-over study designed to elucidate the speed of entrainment in response to a high-fat diet.

Trial Health

57
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
14

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Apr 2022

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

January 28, 2021

Completed
11 days until next milestone

First Posted

Study publicly available on registry

February 8, 2021

Completed
1.1 years until next milestone

Study Start

First participant enrolled

April 1, 2022

Completed
4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 31, 2026

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

March 31, 2026

Completed
Last Updated

November 10, 2025

Status Verified

November 1, 2025

Enrollment Period

4 years

First QC Date

January 28, 2021

Last Update Submit

November 5, 2025

Conditions

Diet, High-FatCircadian Rhythm

Keywords

Circadian RhythmHigh FatDiet

Outcome Measures

Primary Outcomes (1)

  • Change in Speed of entrainment

    Entrainment will be determined as a stable phase angle between sleep and both melatonin onset. Blood and/or saliva will be assayed for melatonin using standardized assays. Melatonin onset will be calculated using the linear interpolated time at which melatonin levels reach 25% of a fitted peak-to-trough amplitude. This will be analyzed using phase angle between sleep and melatonin onset.

    Over 18 days

Secondary Outcomes (20)

  • Change in Phase Angle of entrainment

    Over 18 days

  • Change in Core Body Temperature Entrainment

    Over 18 days

  • Change in Core Body Temperature Phase angle of Entrainment

    Over 18 days

  • Change in glucose tolerance

    Over 18 days

  • Change in Energy Metabolism

    Over 18 days

  • +15 more secondary outcomes

Study Arms (2)

High-Fat Diet

EXPERIMENTAL

50% fat, 35% carbohydrate and 15% protein; 33% of each mono, poly and saturated fat

Other: High-Fat Diet

Low-Fat Diet

ACTIVE COMPARATOR

30% fat, 55% carbohydrate and 15% protein

Other: Low-Fat Diet

Interventions

High-Fat DietOTHER

The diet will consist of a breakfast, lunch, dinner, and snack

High-Fat Diet
Low-Fat DietOTHER

The diet will consist of a breakfast, lunch, dinner, and snack

Low-Fat Diet

Eligibility Criteria

Age18 Years - 40 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • Healthy, lean men and women

You may not qualify if:

  • Major dietary restrictions (such as entirely dairy-free and/or meat-free diets)
  • A body mass index (BMI) of 18.5\< \[BMI\] \< 24.9 kg/m\^2 and a waist circumference \<94/80cm
  • Currently psychiatrically/psychologically unsuitable for participation
  • Drug/alcohol use, including smoking
  • Medication/drug use, including prescribed and over-the-counter medications
  • History of working irregular day and night hours, regular night work, or rotating shift work for the 1 year prior to the study.
  • Traveled across more than 1 time zone during the 3 months prior to the study
  • Currently consuming a habitual high-fat diet
  • Chronobiologic and sleep disorders
  • Diseases of the Cardiovascular System
  • Metabolic Syndrome; Two or more of these factors will be excluded from the study:
  • HDL cholesterol of less than 40 mg/dL in men or less than 50 mg/dL in women;
  • systolic blood pressure\>135 mmHg or diastolic blood pressure\>85 mmHg;
  • Fasting blood glucose ≥ 100 mg/dL;
  • Triglycerides ≥ 150 mg/dL.
  • +12 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Oregon Health & Science University

Portland, Oregon, 97239, United States

RECRUITING

MeSH Terms

Interventions

Diet, High-FatDiet, Fat-Restricted

Intervention Hierarchy (Ancestors)

DietNutritional Physiological PhenomenaDiet, Food, and NutritionPhysiological PhenomenaDiet TherapyNutrition TherapyTherapeutics

Study Officials

  • Andrew McHill, PhD

    Oregon Health and Science University

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Andrew McHill, PhD

CONTACT

503-494-2594mchill@ohsu.edu

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Masking Details
As it will be easy to discern meal fat content, participant blinding is not possible. Participants will be blinded to clock time and light-dark cues and statisticians will be blinded of condition.
Purpose
OTHER
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Principal Investigator

Study Record Dates

First Submitted

January 28, 2021

First Posted

February 8, 2021

Study Start

April 1, 2022

Primary Completion

March 31, 2026

Study Completion

March 31, 2026

Last Updated

November 10, 2025

Record last verified: 2025-11

Data Sharing

IPD Sharing
Will not share

Locations

US(1)