Pilot Study of Isocaloric Time Restricted Eating on Ketone Metabolism and Immunoregulation
Recruiting · Bethesda, Maryland
Always free
Study care at no cost to you
For your time and travel
Many studies pay you back
Most need no insurance or papers
Legal status usually isn't required; we'll tell you each study's requirements
Interpreters available
Ask for your language
Your choice
Voluntary — you can stop anytime
What is this study?
Background: Time restricted eating (TRE) is a form of fasting in which a person eats only during a set window of time, which is usually between 4 and 10 hours each day. Researchers want to know more about how TRE may affect health.
It is , overseen by an independent and licensed medical staff.
Read the full clinical description
Background: Time restricted eating (TRE) is a form of fasting in which a person eats only during a set window of time, which is usually between 4 and 10 hours each day. Researchers want to know more about how TRE may affect health. Objective: To learn how TRE affects women with different body sizes. Eligibility: Healthy women aged 18 to 50 years. Design: Participants will have 2 visits: 1 screening visit and one 5-day stay in the clinic. Participants will fast before both visits. They will have a physical exam with blood tests. They will talk to a nutritionist about the foods they eat. They will lay under a clear hood for up to 45 minutes during a test that measures how many calories they burn while resting. Participants will keep a food diary for up to 7 days before their clinic stay. They will apply a continuous glucose monitor the day before they go to the clinic. This is a device that attaches to the skin of the stomach. They will wear this device throughout their clinic stay. All meals will be provided during the clinic stay. Participants will follow TRE on 3 days. They will answer survey questions and have tests during their stay, including: * DXA (dual energy X-ray absorptiometry) scan. Participants will lie on a padded table. Their body will be scanned to measure how much muscle, bone, fat, and other tissues they have. * Stable isotope tracer study. Small amounts of sugar and other substances will be given through a tube attached to a needle inserted into a vein in the arm. Blood samples will be collected.
Who this study is looking for
In plain language, from the study's own rules. The study team confirms the full details with you — this isn't a final yes or no.
✅ You may be able to join if…
- •Women ages 18 to 50 years
- •Premenopausal (regular periods and/or FSH is below the lab’s upper limit of normal)
- •BMI between 18 and 24.9 or BMI 30 or higher (BMI = body mass index)
- •In good general health, based on medical history and/or screening blood tests
- •Willing to follow all study steps and lifestyle guidance during the study
🚫 You may not be able to join if…
- •Anyone with an immune/inflammatory disorder or other metabolic condition that could affect the study results, including diabetes, chronic kidney disease, chronic liver disease, history of low blood sugar (hypoglycemia), or thyroid disease (except controlled hypothyroidism with normal TSH)
- •Anyone taking medicines that affect blood sugar, use systemic steroids, take adrenergic-stimulating agents, or take other medicines that affect sleep/circadian rhythms/metabolism (examples listed include oral contraceptives, anti-diabetic agents, nicotinamide riboside, tryptophan, and vitamin B3 supplements)
- •People who drink more than about 300 mg of caffeine per day (about three 8-oz cups of coffee)
- •People with sleep/eating schedules that affect circadian rhythms (overnight shift work, irregular sleep/eating schedules) or who usually fast more than 15 hours/day
- •Pregnant or breastfeeding, or unable to provide informed consent
Are you a good fit?
Simplified highlights. The study team always confirms the full details with you.
- ✓Adults roughly 18–50
- ✓A BMI around 30 or higher
- ✓Have Obesity / overweight
- !Not for people who are pregnant or breastfeeding
What to expect, step by step
- 1
Usually a few weeks
The study team checks whether the study is a good fit for you, with a visit and sometimes lab tests. You can ask any questions before deciding.
- 2
Treatment
If you join and choose to continue, you receive the study treatment and are watched closely by medical staff.
- 3
Follow-up
After treatment, the team checks on your health and confirms the visit schedule with you. You can leave the study at any point.
Has this treatment been tested before?
The study team can share what safety testing has been done so far.
What you need to know before you apply
What is this study testing?+
Background: Time restricted eating (TRE) is a form of fasting in which a person eats only during a set window of time, which is usually between 4 and 10 hours each day. Researchers want to know more about how TRE may affect health.
Is it safe? Who makes sure of that?+
This is a research study. Every study is reviewed and monitored by an independent ethics board (called an IRB) whose job is to protect participants, and care is overseen by licensed medical staff. You'll be told the known risks before you agree to anything, and you can stop at any time.
Will I get a placebo instead of the real treatment?+
Some studies compare a treatment against a placebo (an inactive version), and some don't. If this one does, the study team will explain your chances of receiving the active treatment before you decide. Nothing is hidden from you.
Do I have to stop taking my current medications?+
It depends on the study. Some let you stay on your current medications and some ask you to adjust them. Never stop a medication on your own — the study team will review everything with you first.
Does it cost anything? Will I be paid?+
Study-related care is provided at no cost to you. Some studies also pay for your time; the coordinator can tell you if this one does. You should never be asked to pay to take part.
Do I need insurance? Will anyone ask about my immigration status?+
No. You do not need health insurance to take part in a research study, and you will not be asked about your immigration status to join. Taking part is about whether you're a medical fit for the study.
What if English isn't my first language?+
You have the right to understand everything before you agree. Study sites can often provide materials or an interpreter in your language — you can ask the coordinator for one.
Is my information private?+
Yes. Your health information is only shared with the study sites you choose to be contacted by, and only to help match and enroll you. It is never sold, and you can ask us to delete it at any time.
Some requirements (like specific lab values or timing) are confirmed directly by the study team, not by us.
Source: ClinicalTrials.gov · NCT06169137 · Locations: Maryland