SleepNCT07138313
Dietary Impact on Sleep, Rhythms and Related Physiology
A study testing Low-fat dietary intervention and High-fat dietary intervention in people with Sleep and Diet Interventions, run by Uppsala University at 1 site in Sweden.
Trial summary
Sleep and metabolism are closely interconnected, and emerging evidence suggests that dietary composition may influence both sleep quality and key physiological functions such as glucose regulation, cardiovascular activity, and hormonal signaling. Read more about this study
- Who is it for?
- Ages 18 to 32 yearsHealthy volunteers can take part
- Conditions the study is for
- Sleep, Diet Interventions, Circadian Rhythm
- What is being tested?
- Low-fat dietary intervention and High-fat dietary intervention
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 24 participants
- Where
- 1 siteSweden
- Study dates
- 22 Sep 2025to 31 Dec 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 32 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Age 18-32 yr
- Healthy (self-reported) and not on chronic medication
- BMI 18-27 kg/m2 (and waist circumference <102 cm), and weight stable (less than 5% body weight change in the past 6 months)
- Non-smoker and non-nicotine user
- Regular sleep-wake pattern, with sleep duration of 7-9.25 hrs per night
- Regular exercise habits the last 2 months
- Regular daily meal pattern with 3 main meals
Who cannot join
- Major or chronic illness, e.g. diabetes, renal disease or inflammatory bowel disease
- Current or history of endocrine or metabolic disorders
- Psychiatric or neurological disorders (e.g. bipolar disorder, epilepsy)
- Frequent gastrointestinal symptoms
- Chronic medication
- Any sleep disorder (including recent or chronic symptoms of insomnia)
Show all 14Show fewer
- Shift work in the preceding three months or for a long duration
- Extreme chronotype or physical activity patterns
- Time travel over two time zones in the preceding month
- Too much weight gain or weight loss in the preceding 6 months (±5% body weight in past 6 months)
- Any issues with or allergies against the provided food items
- Recent major dietary changes or adoption of specific dietary regimens
- Women who are pregnant, breastfeeding, or planning to become pregnant during the study period.
- Use of illicit drugs or substances of abuse
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Sweden1 site, 1 recruiting
- Recruiting
Uppsala biomedical center
Uppsala, 75324
Jonathan Cedernaes, MD PhD, 004618-617 32 93, jonathan.cedernaes@medsci.uu.se
Jonathan Cedernaes, MD PhD
About this study
Official title: Inverkan av Kost pa Dygnsrytmer Och Amnesomsattning
Sleep and metabolism are closely interconnected, and emerging evidence suggests that dietary composition may influence both sleep quality and key physiological functions such as glucose regulation, cardiovascular activity, and hormonal signaling. This study aims to investigate how a Western-style unhealthy diet versus a healthier, fiber-rich diet affects objective and subjective sleep measures, 24-hour physiological parameters, and a range of biomarkers related to cardiometabolic, neurodegenerative, and gut microbial function.
Read the detailed description
Metabolism is tightly regulated by sleep and interacts bidirectionally with diet. While it is well established that insufficient or disrupted sleep can impair glucose regulation, cardiovascular function, and promote unhealthy eating behaviors that promote cardiometabolic disease, less is known about how different dietary patterns impact subjective and objective sleep parameters, as well as related physiological systems.
The study will systematically investigate how consumption of an unhealthier "Western" diet, compared to a healthier diet, affects both objective and subjective sleep parameters, as well as 24-hour heart rate and blood pressure profiles, glucose variability, and hormonal and molecular biomarkers.
The study will be conducted as a 2-condition, randomized crossover study, with assessments in the field for about a week, followed by a multi-day stay for measurements under standardized laboratory conditions. Participants will be monitored using polysomnography, and wearable devices, including for continuous glucose and heart rate parameters, with multi-compartment sampling to assess diet-mediated responses across cardiometabolic, neurodegenerative, and microbial pathways. In field and in the lab, biological samples will be collected repeatedly across the day to establish diurnal rhythms.
Cognitive performance, mood, and subjective appetite will also be evaluated. By identifying diet-driven changes in sleep and related physiological functions, this study aims to provide mechanistic insights into how nutrition impacts sleep, cardiometabolic health parameters and molecular pathways.
- Conditions
- Sleep, Diet Interventions, Circadian Rhythm
- Being tested
- Low-fat dietary intervention, High-fat dietary intervention
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Low-fat dietary interventionOther
Low-fat diet for approximately 1 week, preceding in-lab study period (approximately 2 days) under standardized conditions (total dietary exposure up to 9-10 days).
High-fat dietary interventionOther
High-fat diet for approximately 1 week, preceding in-lab study period (approximately 2 days) under standardized conditions (total dietary exposure up to 9-10 days).
| Study group | Role | What they receive |
|---|---|---|
| Healthy diet | Experimental | 'Low-fat dietary intervention' to be administered to participants Receives: Other: Low-fat dietary intervention |
| Unhealthier diet | Experimental | 'High-fat dietary intervention' to be administered to participants Receives: Other: High-fat dietary intervention |
What is being measured
The primary outcome is the main question the study is designed to answer.
Sleep Architecture and Neurophysiological Features
Objective registration and analysis of sleep, based on polysomnography or validated wearable devices to capture macrosleep, spectral and microsleep features.
Measured: Up to 9 nights on each diet
Change in 24-Hour Heart Rate Variability (HRV)
Continuous measurement of HRV, using a wearable device, focused on the metric Root Mean Square of the Successive Differences (RMSD); additional metrics (Standard Deviation of NN intervals (SDNN), low frequency to high frequency (LF/HF) ratio) analyzed for exploratory purposes.
Measured: Up to 9 days on each diet
Secondary outcomes (24)
24-Hour Heart Rate (HR)
Continuous measurement of heart rate using a wearable device
Measured: Up to 9 days on each diet
Heart Rate Response to Standardized Stair Stepping
ECG-based heart rate measured at baseline, during stepping and repeatedly (up to 5 min) post-stair stepping, to assess recovery, also analyzed in relation to sleep metrics.
Measured: Baseline and day 7-9 of each diet period
Morning-to-Evening and 24-h blood pressure (BP)
Morning, evening, and 24-h ambulatory measurement of systolic blood pressure, also analyzed in relation to sleep metrics.
Measured: Up to 9 days on each diet
24 Hour Continuous Glucose Levels
Continuous (24-h) monitoring of interstitial glucose for analysis of mean levels and variability metrics (e.g., SD, coefficient of variation, postprandial changes), also analyzed in relation to sleep metrics.
Measured: Up to 9 days on each diet
Levels of Blood-based Biomarkers
Changes in levels of molecular factors such as DNA, hormones/proteins and metabolites, due to the preceding dietary intervention, and also in relation to sleep metrics.
Measured: Up to 9 days on each diet
Levels of CNS biomarkers
Levels of CNS health biomarkers (such as brain-derived neurotrophic factor (BDNF), Tau (e.g. BD-tau) and Amyloid beta (Aβ) species, glial fibrillary acidic protein (GFAP), and Neurofilament light chain (NfL)).
Measured: Up to 9 days on each diet
Urinary Metabolite Levels
Urine levels of excretion molecules (such as melatonin breakdown metabolites).
Measured: Up to 9 days on each diet
Change in Metabolic Fuel Utilization
Change in metabolic fuel utilization as measured by respirometry, in response to the dietary interventions.
Measured: Up to 9 days on each diet
Levels of Fecal Metabolites
Changes in levels of fecal metabolites (such as short chain fatty acids, bile acids) due to each dietary intervention
Measured: Up to 9 days on each diet
Levels of Fecal Microbiota
Changes in fecal microbiota (metagenomic, compositional) due to each dietary intervention
Measured: Up to 9 days on each diet
Levels of Salival Biomarkers
Changes in levels of salival molecules (such as cortisol and melatonin), also in relation to sleep-circadian metrics.
Measured: Up to 9 days on each diet
Levels of Salival Microbiota
Changes in salival microbiota (metagenomic, compositional) due to each dietary intervention
Measured: Up to 9 days on each diet
Changes in glucose tolerance
Glucometabolic response to a standardized 2-h glucose tolerance test, also analyzed in relation to sleep-circadian metrics.
Measured: Day 8-9 on each diet
Levels of Immune Cells
Immune cell profile across the day in response to each diet
Measured: Up to 9 days on each diet
Change in Subjective Sleep Quality
Change in self-reported sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI), supplementing objective sleep data. Total Score (0-21; higher = worse).
Measured: Up to 9 days on each diet
Subjective Hunger and Appetite Levels
Self-reported hunger and appetite across the day, and prior to and after meals, as assessed via visual analogue scales (VAS, i.e., with scores 0 for the lowest subjective rating, to 100 for the highest rating)
Measured: Up to 9 days on each diet
Body Temperature
Body temperature measured via wearable sensors to assess effects of dietary interventions on thermoregulation and its relationship to sleep, circadian rhythms and metabolism.
Measured: Up to 9 days on each diet
Change in Composite Cognitive Performance Score
Composite score from four tasks:
- Psychomotor Vigilance Task (PVT) - sustained attention; faster reaction times and fewer lapses corresponds to better performance;
- Go/No-Go Task - inhibitory control; higher accuracy on no-go trials and faster correct go responses corresponds to better performance;
- Task-Switching Task - cognitive flexibility; smaller switch cost (difference in reaction time between switch and repeat trials) and higher accuracy corresponds to better performance;
- Memorability Task - episodic memory; higher hit rate (0-100%) and fewer false alarms corresponds to better performance.
All scores will be standardized and averaged; higher composite values indicate better cognitive performance.
Measured: Up to 9 days on each diet
Changes in mental wellbeing
Self-reported assessment of mental wellbeing using validated subjective scales (visual analogue scales going from lowest 0 to highest of 100), to evaluate effects of diet and sleep.
Measured: Up to 9 days on each diet
Changes in Central Hemodynamics
Morning, evening, and 24-h ambulatory levels of central hemodynamics reflecting central blood pressure and arterial resistance, also analyzed in relation to sleep metrics
Measured: Up to 9 days on each diet
Effect Modification by Biological Sex
Exploratory subgroup analysis to determine if male vs. female participants differ in response to dietary interventions, for primary and secondary outcomes
Measured: Based on data collected up to 9 days on each diet
Effect Modification by Cardiorespiratory Fitness
Exploratory analysis to determine whether cardiorespiratory fitness parameters modulates responses to how the diets impact primary and secondary outcomes.
Measured: Based on data collected up to 9 days on each diet
Change in Dim Light Melatonin Onset
Dim Light Melatonin Onset as assessed via repeatedly measured melatonin levels, measured in the evening under standardized conditions
Measured: Up to 9 days on each diet
Levels of molecular biomarkers in dried blood spots
Analysis of levels of molecular biomarkers (such as CRP) in dried blood spots from finger samples, and how these correlate with biomarker levels from peripheral venous blood samples
Measured: Up to 9 days on each diet
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Aug 2025
- Study start22 Sep 2025
- Primary completion31 Jul 2027 (estimated)
- Study completion31 Dec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for SleepStudies of the same condition, open and under way.
- More trials run by Uppsala UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Participants will be studied in a crossover design both after a "healthy diet", and after an "unhealthy diet"
- Masking
- None (open label)
- Enrolment
- 24 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Uppsala University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Jonathan Cedernaes, MD, PhD, Principal investigator, Uppsala University, Sweden
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07138313
- Sponsor's protocol ID
- CircHFJC2017pt2
- Status last verified
- Feb 2026
- First submitted
- 4 Jul 2025
- Last updated
- 4 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 4 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Inverkan av Kost pa Dygnsrytmer Och Amnesomsattning
- ClinicalTrials.gov ID
- NCT07138313
- Acronym / sponsor ID
- CircHFJC2017pt2
- Conditions
- Sleep, Diet Interventions, Circadian Rhythm
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 24 participants (estimated)
- Lead sponsor
- Uppsala UniversityUniversity, hospital or other
- Study start
- 22 Sep 2025 (actual)
- Primary completion
- 31 Jul 2027 (estimated)
- Study completion
- 31 Dec 2027 (estimated)
- First posted
- 22 Aug 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Sleep and metabolism are closely interconnected, and emerging evidence suggests that dietary composition may influence both sleep quality and key physiological functions such as glucose regulation, cardiovascular activity, and hormonal signaling. This study aims to investigate how a Western-style unhealthy diet versus a healthier, fiber-rich diet affects objective and subjective sleep measures, 24-hour physiological parameters, and a range of biomarkers related to cardiometabolic, neurodegenerative, and gut microbial function.
Detailed description
Metabolism is tightly regulated by sleep and interacts bidirectionally with diet. While it is well established that insufficient or disrupted sleep can impair glucose regulation, cardiovascular function, and promote unhealthy eating behaviors that promote cardiometabolic disease, less is known about how different dietary patterns impact subjective and objective sleep parameters, as well as related physiological systems.
The study will systematically investigate how consumption of an unhealthier "Western" diet, compared to a healthier diet, affects both objective and subjective sleep parameters, as well as 24-hour heart rate and blood pressure profiles, glucose variability, and hormonal and molecular biomarkers.
The study will be conducted as a 2-condition, randomized crossover study, with assessments in the field for about a week, followed by a multi-day stay for measurements under standardized laboratory conditions. Participants will be monitored using polysomnography, and wearable devices, including for continuous glucose and heart rate parameters, with multi-compartment sampling to assess diet-mediated responses across cardiometabolic, neurodegenerative, and microbial pathways. In field and in the lab, biological samples will be collected repeatedly across the day to establish diurnal rhythms.
Cognitive performance, mood, and subjective appetite will also be evaluated. By identifying diet-driven changes in sleep and related physiological functions, this study aims to provide mechanistic insights into how nutrition impacts sleep, cardiometabolic health parameters and molecular pathways.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Participants will be studied in a crossover design both after a "healthy diet", and after an "unhealthy diet"
| Arm | Type | Receives |
|---|---|---|
| Healthy diet | Experimental | Other: Low-fat dietary intervention'Low-fat dietary intervention' to be administered to participants |
| Unhealthier diet | Experimental | Other: High-fat dietary intervention'High-fat dietary intervention' to be administered to participants |
Who may qualify
- Ages
- 18 to 32 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (7 listed)
- Age 18-32 yr
- Healthy (self-reported) and not on chronic medication
- BMI 18-27 kg/m2 (and waist circumference <102 cm), and weight stable (less than 5% body weight change in the past 6 months)
- Non-smoker and non-nicotine user
- Regular sleep-wake pattern, with sleep duration of 7-9.25 hrs per night
Key exclusion criteria (14 listed)
- Major or chronic illness, e.g. diabetes, renal disease or inflammatory bowel disease
- Current or history of endocrine or metabolic disorders
- Psychiatric or neurological disorders (e.g. bipolar disorder, epilepsy)
- Frequent gastrointestinal symptoms
- Chronic medication
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Low-fat dietary interventionLow-fat diet for approximately 1 week, preceding in-lab study period (approximately 2 days) under standardized conditions (total dietary exposure up to 9-10 days). | Other | Healthy diet |
| High-fat dietary interventionHigh-fat diet for approximately 1 week, preceding in-lab study period (approximately 2 days) under standardized conditions (total dietary exposure up to 9-10 days). | Other | Unhealthier diet |
Primary outcome
Sleep Architecture and Neurophysiological Features
Time frame: Up to 9 nights on each diet
Objective registration and analysis of sleep, based on polysomnography or validated wearable devices to capture macrosleep, spectral and microsleep features.
Change in 24-Hour Heart Rate Variability (HRV)
Time frame: Up to 9 days on each diet
Continuous measurement of HRV, using a wearable device, focused on the metric Root Mean Square of the Successive Differences (RMSD); additional metrics (Standard Deviation of NN intervals (SDNN), low frequency to high frequency (LF/HF) ratio) analyzed for exploratory purposes.
24 secondary outcomes
24-Hour Heart Rate (HR)
Time frame: Up to 9 days on each diet
Heart Rate Response to Standardized Stair Stepping
Time frame: Baseline and day 7-9 of each diet period
Morning-to-Evening and 24-h blood pressure (BP)
Time frame: Up to 9 days on each diet
24 Hour Continuous Glucose Levels
Time frame: Up to 9 days on each diet
Levels of Blood-based Biomarkers
Time frame: Up to 9 days on each diet
Levels of CNS biomarkers
Time frame: Up to 9 days on each diet
Urinary Metabolite Levels
Time frame: Up to 9 days on each diet
Change in Metabolic Fuel Utilization
Time frame: Up to 9 days on each diet
Levels of Fecal Metabolites
Time frame: Up to 9 days on each diet
Levels of Fecal Microbiota
Time frame: Up to 9 days on each diet
Levels of Salival Biomarkers
Time frame: Up to 9 days on each diet
Levels of Salival Microbiota
Time frame: Up to 9 days on each diet
Changes in glucose tolerance
Time frame: Day 8-9 on each diet
Levels of Immune Cells
Time frame: Up to 9 days on each diet
Change in Subjective Sleep Quality
Time frame: Up to 9 days on each diet
Subjective Hunger and Appetite Levels
Time frame: Up to 9 days on each diet
Body Temperature
Time frame: Up to 9 days on each diet
Change in Composite Cognitive Performance Score
Time frame: Up to 9 days on each diet
Changes in mental wellbeing
Time frame: Up to 9 days on each diet
Changes in Central Hemodynamics
Time frame: Up to 9 days on each diet
Effect Modification by Biological Sex
Time frame: Based on data collected up to 9 days on each diet
Effect Modification by Cardiorespiratory Fitness
Time frame: Based on data collected up to 9 days on each diet
Change in Dim Light Melatonin Onset
Time frame: Up to 9 days on each diet
Levels of molecular biomarkers in dried blood spots
Time frame: Up to 9 days on each diet
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 4 Feb 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Jonathan Cedernaes, MD, PhD principal investigator
Uppsala University, Sweden
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Low-fat dietary intervention and High-fat dietary intervention in people with Sleep and Diet Interventions, run by Uppsala University at 1 site in Sweden.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 14 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 4 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Sweden. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Jonathan Cedernaes, MD, PhD (0184710000, jonathan.cedernaes@medsci.uu.se), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Sleep Architecture and Neurophysiological Features (time frame: Up to 9 nights on each diet). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 4 Feb 2026.