The Short Sleep Study
1 other identifier
observational
34
1 country
4
Brief Summary
Natural Short Sleepers are defined as individuals who sleep fewer than 6 hours per night without any impact on health or daytime mental fatigue levels. Emerging evidence suggests that, in the general population, the gut microbiota would be negatively influenced by this sleep duration. It is possible that Natural Short Sleepers have a distinct gut microbiome. Identifying differences in microbiota composition may lead to an opportunity to improve health outcomes in those with inadequate or poor sleep.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P25-P50 for all trials
Started Oct 2025
Shorter than P25 for all trials
4 active sites
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
Study Start
First participant enrolled
October 23, 2025
CompletedFirst Submitted
Initial submission to the registry
November 10, 2025
CompletedFirst Posted
Study publicly available on registry
May 5, 2026
CompletedPrimary Completion
Last participant's last visit for primary outcome
September 1, 2026
ExpectedStudy Completion
Last participant's last visit for all outcomes
November 1, 2026
May 5, 2026
November 1, 2025
10 months
November 10, 2025
April 30, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (2)
Microbiome characterization of the short sleeper population
Identify a specific fecal microbiota composition related to short sleep
baseline through day 10 of the study period.
Comparison of natural short sleeper microbiomes to participants from the night owl study.
Compare microbiome (composition and function) of natural short sleeprs to those individuals enrolled into the night owl study.
From baseline through day 10 of the study period.
Study Arms (1)
Natural Short Sleepers
Natural short sleepers (NSS) sleep on average \<6 hours per night, but feel no need to sleep longer, and do not show signs of daytime sleepiness or fall asleep in low stimulus environments.
Eligibility Criteria
Natural Short Sleepers are defined as individuals who sleep between 4 and 5.5 hours per night without any impact on health or daytime mental fatigue levels.
You may qualify if:
- Men between 20 - 50 years of age and pre-menopausal women between 20 - 45 years of age (inclusive).
- Consistent schedule during daytime hours.
- Body Mass Index (BMI) 18.5 - 35 kg/m2 (inclusive).
- Good physical and mental health as established by self-reported medical history and evaluated by a study investigator.
- Willingness to maintain and record their general habits, eating, and daily activity/exercise pattern for the study period.
- Willingness to maintain typical sleep hygiene patterns (e.g. sleep location, temperature, environment).
- Willingness to maintain their current pattern of alcohol consumption for the duration of the study.
- Willing and able to participate fully in all aspects of the study and complete all study procedures, including providing signed informed consent.
- Willing and able to attend two in-person visits at a trial site
- Completes all required procedures (screening questionnaire and ePROs) during the 14-day screening period 10a. Two instances of the sleep diary and Karolinska Sleepiness Scale may be missed by the participant without impacting eligibility
- Has regular bowel habits, on at least 5 days a week.
- Pittsburgh Sleep Quality Index (PSQI) score≤5 self-reported during the screening period.
- Sleep, on average, 4-5.5 hours per night, verified via participant self-report during the screening period. If the participant's average is within the 4-5.5 hour range but slept more than 5.5 hours on any of the nights their eligibility will be assessed per PI/Sponsor discretion. Note: Oura ring data from the run-in period will be reviewed to confirm eligibility based on PI/Sponsor discretion.
- Report feeling refreshed with no desire to nap during the daytime, with a score of ≤4 on the Epworth Sleepiness Scale (ESS) evaluated during the screening period.
- Average KSS Score of 1-3 during the screening period.
You may not qualify if:
- Ever diagnosed with or self-reports a sleep disorder, including sleep apnea, habitual snoring (defined as loud, persistent snoring 3 or more nights per week), insomnia, narcolepsy, or parasomnias.
- Extreme chronotypes, those who regularly go to sleep prior to 8:00pm.
- Any current diagnosed or self-reported gastrointestinal disorder, including Crohn's disease, ulcerative colitis, celiac disease, IBS, or functional bowel disorder or chronic heartburn.
- Regularly wakes up during the night 5 or more times per night for a cumulative amount of 30 minutes as observed via self-report during the screening period, per PI discretion.
- Currently taking medications (including over-the-counter medications) or dietary supplements that, in the investigator's opinion, may affect the participants' microbiome or sleep.
- Have taken in the last 3 months medications (including over-the-counter medications) or dietary supplements that, in the investigator's opinion, may affect the participants' microbiome or sleep.
- Neurodegenerative diseases (including multiple sclerosis, Parkinson's disease, Alzheimer's disease, dementia).
- Recent history (past year) of alcohol abuse or dependence. Defined as regularly drinking more than 12 drinks for females and more than 20 drinks for males per week and based on PI discretion.
- Drug abuse or dependence, including consistent recreational substance use such as marijuana.
- Binge drinking behavior, defined as 4 or more alcoholic drinks for women or 5 or more alcoholic drinks for men in one sitting on 2 or more occasions, within the past 1 month with final decision per PI discretion.
- Recent history (current use or within the past 1 month) of smoking, vaping or other use of nicotine-containing products.
- Diagnosed neuropsychiatric disorders or symptoms possibly affecting sleep e.g. (generalized anxiety disorder (GAD), major depressive disorder (MDD), bipolar disorder, schizophrenia)
- Any use of systemic antibiotics in the past 3 months. This does not include topical or targeted antibiotic use (ointment, spray, eye drop, ear drop).
- Any use of probiotic supplements in the past 2 weeks.
- Any use of proton pump inhibitors (PPIs) in the past 2 weeks.
- +9 more criteria
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Daniscolead
Study Sites (4)
Global Life Research Network
Miami, Florida, 33155, United States
Lindus Health
Boston, Massachusetts, 02111, United States
AccuMed
Garden City, New York, 11530, United States
New Dawn Wellness and Medical Research Center
Houston, Texas, 77082, United States
Biospecimen
Fecal microbiota and metabolome
Study Design
- Study Type
- observational
- Observational Model
- COHORT
- Time Perspective
- PROSPECTIVE
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
November 10, 2025
First Posted
May 5, 2026
Study Start
October 23, 2025
Primary Completion (Estimated)
September 1, 2026
Study Completion (Estimated)
November 1, 2026
Last Updated
May 5, 2026
Record last verified: 2025-11
Data Sharing
- IPD Sharing
- Will not share