Does Circadian Misalignment Have Sex-Specific Effects on Metabolism?

Role of Biological Sex in Metabolic Responses to Night Work

This study will test whether biological sex influences how the body responds to circadian misalignment-a mismatch between the internal body clock and the timing of sleep and eating (as can occur with shift work or jet lag). Researchers will examine how circadian misalignment affects appetite regulation (hunger/fullness) and glucose metabolism (blood sugar control), and whether these effects differ between females and males. Findings may help inform more personalized shift work schedules and targeted strategies to reduce metabolic health risks and sex-related differences in clinical care.

Study Overview

• Status: Not yet recruiting
• Conditions: Sex Differences; Circadian Misalignment
• Intervention / Treatment: Behavioral: Day shift; Behavioral: Night shift

Detailed Description

This study will examine whether biological sex affects how the body responds to circadian misalignment-a mismatch between a person's internal body clock and their sleep/wake and eating schedule (similar to what can happen with night shift work, jet lag, or frequently changing sleep schedules). Researchers will measure how circadian misalignment influences appetite regulation (such as hunger and fullness) and glucose metabolism (how the body controls blood sugar), and whether these effects differ between females and males.

By identifying sex-specific responses to circadian misalignment, this research may help guide the development of safer, more personalized shift work schedules and targeted strategies to reduce metabolic health risks, with the goal of improving clinical care and reducing sex-related differences in metabolic disease risk.

• Study Type: Interventional
• Enrollment (Estimated): 36
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jingyi Qian, PhD; Phone Number: 617-525-7423; Email: jqian5@mgb.org

Study Locations

• United States
  • Massachusetts
    • Boston, Massachusetts, United States, 02115
      • Brigham and Women's Hospital
      • Contact: Vy Nguyen, B.S.; Phone Number: (617)-525-0662; Email: vnguyen42@bwh.harvard.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• 18-40 years of age
• Body Mass Index 18.5-24.9 kg/m2
• Non-smokers, no current tobacco or e-cigarette use
• Healthy with no acute or chronic medical and psychiatric disorders
• Sex assigned at birth consistent with reproductive anatomy at enrollment (per protocol definition)

Exclusion Criteria:

• History of drug or alcohol dependency
• History of psychiatric illness or disorder
• Pregnant
• No prior gender-affirming hormone therapy and no gonadectomy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Day Shift -> Night Shift; Day Shift protocol first, then Night Shift protocol	Behavioral: Day shift; Research participants will be assigned to day shift condition in which sleep-wake and meal schedules are aligned with the internal circadian system; Behavioral: Night shift; Research participants will be assigned to simulated night shift condition in which sleep-wake and meal schedules are misaligned with the internal circadian system
Experimental: Night shift -> Day shift; Night shift protocol first, then Day Shift protocol	Behavioral: Day shift; Research participants will be assigned to day shift condition in which sleep-wake and meal schedules are aligned with the internal circadian system; Behavioral: Night shift; Research participants will be assigned to simulated night shift condition in which sleep-wake and meal schedules are misaligned with the internal circadian system

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difference in circulating leptin levels between Night Shift and Day Shift	Differences of 24-h circulating leptin levels on the test days in the two experimental conditions	24 hours
Differences in Disposition index (DI) derived from identical test breakfast between Night Shift and Day Shift	Disposition index (DI) derived from oral minimal model based on postprandial glucose, insulin, and c-peptide responses to identical test breakfast on the test days between protocols	3 hours
Differences in self-rated cravings for hyperpalatable food during the wake period between Night Shift and Day Shift.	Differences in self-rated cravings for hyperpalatable food during the wake period on the test days between protocols.	16 hours

Collaborators and Investigators

• Sponsor: Brigham and Women's Hospital
• Investigators: Principal Investigator: Jingyi Qian, PhD, Brigham and Women's Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): October 1, 2026
• Primary Completion (Estimated): September 30, 2030
• Study Completion (Estimated): September 30, 2030

Study Registration Dates

• First Submitted: February 23, 2026
• First Submitted That Met QC Criteria: February 23, 2026
• First Posted (Actual): February 27, 2026

Study Record Updates

• Last Update Posted (Actual): February 27, 2026
• Last Update Submitted That Met QC Criteria: February 23, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: sex differences; glucose control; circadian rhythm; appetite regulation; night work
• Additional Relevant MeSH Terms: Organization and Administration; Health Services Administration; Personnel Management; Personnel Staffing and Scheduling; Shift Work Schedule
• Other Study ID Numbers: 2026P000307

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No