This Trial Examines How Last Meal Composition and Timing Affect Sleep Quality and Circadian Gene Expression Among Medical Residents. Recruitment Not Yet Started; Study Begins Dec 2025 and Ends Dec 2026.
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: High-Carbohydrate Last Meal, High-Protein Last Meal, Balanced Standard Dinner.
- Who it may be relevant to
- Registry conditions: Sleep Quality, Meal Timing, Circadian Rhythm, Medical Residents. Basic parameters: from 25 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Jordan
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
CHRONO-NUTRITION INTERVENTIONS FOR IMPROVING SLEEP QUALITY: The Impact of Last Meal Composition and Timing on Sleep Quality Among Medical Residents at Hospitals
Overview
This randomized controlled trial aims to evaluate the effects of last meal composition and timing on sleep quality and circadian gene expression among medical residents in Jordanian hospitals. Sleep disturbances are common in this population due to long working hours, high stress, and irregular eating schedules. Chrono-nutrition, the science of aligning food intake with circadian rhythms, may provide a practical approach to improving sleep and overall well-being. Participants will be randomly assigned to one of three groups: 1. High-carbohydrate last meal (≈80% of dinner calories from carbohydrates), 2. High-protein last meal (≈40-50% of dinner calories from protein), 3. Control group consuming a balanced standard meal. Each participant will consume the assigned meal 3-4 hours before bedtime for two weeks. Sleep quality will be measured using the Pittsburgh Sleep Quality Index (PSQI) and smartwatch-derived parameters, while salivary samples collected pre- and post-intervention will be analyzed for CLOCK and BMAL1 gene expression. The study will also include dietary, anthropometric, and physical activity assessments. This study has been approved by the Institutional Review Board of the University of Jordan (IRB No. 491/2025). Recruitment has not yet started. Enrollment is expected to begin in December 2025, with primary data collection completed by June 2026 and final study completion by December 2026.
Interventions
- Dietary supplement High-Carbohydrate Last Meal
Dinner ≈30% daily kcal; \~80% carb; taken 3-4 h before sleep for 2 weeks - Dietary supplement High-Protein Last Meal
Dinner ≈30% daily kcal; \~38-54% protein; 3-4 h before sleep for 2 weeks. - Dietary supplement Balanced Standard Dinner
Standard macronutrient distribution; same timing (3-4h pre-sleep) and 2-week duration.
Primary outcome measures
- Change in Sleep Quality (PSQI Global Score) [Time frame: Baseline and 2 weeks post-intervention]
Secondary outcome measures (6)
- Change in CLOCK Gene Expression [Time frame: Baseline and 2 weeks post-intervention]
- Change in BMAL-1 Gene Expression [Time frame: Baseline and 2 weeks post-intervention]
- Change in Total Sleep Duration [Time frame: 1 week baseline and 2 weeks during intervention]
- Change in Sleep Efficiency [Time frame: 1 week baseline and 2 weeks during intervention]
- Change in Sleep Stage Distribution [Time frame: 1 week baseline and 2 weeks during intervention]
- Change in Average Heart Rate During Sleep [Time frame: 1 week baseline and 2 weeks during intervention]
Eligibility criteria
Inclusion criteria
- Currently enrolled and working in Jordanian hospitals.
- Not currently following a specific diet or weight-loss program.
- Willing to comply with study protocol and intervention meals for two weeks. Provide written informed consent before participation.
Exclusion criteria
- Presence of any chronic medical condition (e.g., diabetes, thyroid disorders, gastrointestinal, cardiovascular, or respiratory diseases).
- Diagnosed sleep disorders, such as insomnia, sleep apnea, or restless legs syndrome.
- Mental health disorders (stress, anxiety, or depression diagnosed or medicated).
- Pregnancy or lactation.
- Use of medications or herbal supplements known to affect sleep (e.g., melatonin, chamomile, ashwagandha, lavender).
- Caffeine dependence exceeding moderate levels ( >400 mg caffeine/day).
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Allocation
- Randomized
- Model
- Parallel assignment
- Masking
- Double blind
- Primary purpose
- Prevention
Study locations
Jordan · 1 center
- University of Jordan Hospital — Amman
Identifiers
NCT: NCT07339592 · University of Jordan 491/2025