Recruiting

High-Fat Diet

Sponsor:

Oregon Health and Science University

Code:

NCT04743271

Conditions

Diet, High-Fat

Circadian Rhythm

Eligibility Criteria

Sex: All

Age: 18 - 40

Healthy Volunteers: Accepted

Interventions

High-Fat Diet

Low-Fat Diet

Study Details

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.

Conditions

Diet, High-Fat

Circadian Rhythm

Study ID

NCT04743271

Start date

Apr 1, 2022

Status verified date

Nov, 2025

Completion date

Mar 31, 2026

Anticipated

Primary completion date

Mar 31, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 40

Healthy Volunteers: Accepted

Inclusion Criteria:

  • Healthy, lean men and women

Exclusion Criteria:

  • 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:

1. HDL cholesterol of less than 40 mg/dL in men or less than 50 mg/dL in women;
2. systolic blood pressure>135 mmHg or diastolic blood pressure>85 mmHg;
3. Fasting blood glucose ≥ 100 mg/dL;
4. Triglycerides ≥ 150 mg/dL.
  • Pre-Diabetes/Diabetes
  • Hypertension
  • Disorders of the Respiratory System
  • Disorders of the Kidney and Urinary Tract
  • Infectious Diseases
  • Disorders of the Gastrointestinal System
  • Disorders of the Immune System
  • Disorders of the Hematopoietic System
  • Neoplastic Diseases
  • Endocrine and Metabolic Diseases
  • Neurologic Disorders
  • Subjects must not be currently participating in another research study that would influence their safe participation in our study

Study Design

Enrollment

14 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Other

Interventions and Outcome Measures

Arms

experimental: High-Fat Diet

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

active comparator: Low-Fat Diet

30% fat, 55% carbohydrate and 15% protein

Interventions

High-Fat Diet

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

Low-Fat Diet

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

Primary outcome measure

  • Change in Speed of entrainment [ Time Frame: Over 18 days ]

Central Contacts and Locations

Central contacts

Andrew McHill, PhD

503-494-2594mchill@ohsu.edu

Locations

Oregon Health & Science University

Recruiting

Portland, Oregon, United States, 97239

Contacts

Andrew W McHill, PhD

5034942594mchill@ohsu.edu

More Information

Sponsor

Oregon Health and Science University

Last update posted

Nov 10, 2025

Last verified

Nov, 2025

Keywords

  • Circadian Rhythm
  • High Fat
  • Diet

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Oregon Health and Science University on 2025-11-10.