Diet order may matter: Low-Carb first could boost fat loss
NCT ID NCT06325722
First seen Jun 25, 2026 · Last updated Jul 31, 2026 · Updated 6 times
Summary
This study tests whether starting with a low-carb diet and then switching to low-fat leads to more body fat loss than the opposite order. Over 8 weeks, 42 overweight adults will eat only provided meals and track their weight, activity, and glucose. Researchers want to see if diet order makes a real difference when people live at home.
What this could mean
Our plain-language read of the trial. This is informational only, not medical advice or a prediction.
- Active substance
- low-carbohydrate diet and low-fat diet
- What this could lead to
- If it works, this could show that starting with a low-carb diet leads to more fat loss, even when switching diets later.
- What could go wrong
- This is a small, early-stage study with only 42 people. Results may not apply to everyone, and the effect may be small or not repeatable at home.
This is an AI summary of the original study and may miss details. Read our disclaimer.
Study facts
What this study's own registry entry says, in plain language.
- Phase
-
Not a phased trial
Phase numbers describe drug development. The registry uses this when they do not apply, as it does for trials of devices, procedures or behaviour changes, and for observational studies.
- Participants
-
About 42 people
The number the study aims to enrol. It can still change while the study runs.
- Started
-
Aug 2024
- Expected to finish
-
Nov 2029
An estimate. End dates often move.
- Lead sponsor
-
A government research agency
The lead sponsor is the US National Institutes of Health.
Who can take part
This study's own entry requirements. Only the study team can say for certain whether you qualify.
- Ages
-
18 to 50 years
- Sex
-
Anyone
- Healthy volunteers
-
Not accepted
This study is not open to healthy volunteers. The entry requirements below say who it is open to.
Show the full entry requirements Hide the full entry requirements
Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.
* INCLUSION CRITERIA: In order to be eligible to participate in this study, an individual must meet all of the following criteria: 1. Stated willingness to comply with all study procedures and availability for the duration of the study 2. Adults aged 18-50 years 3. Weight stable (\< +/- 5% over past 6 months) as determined by volunteer report 4. Body mass index (BMI) \>= 25 kg/m\^2 5. Agreement to adhere to Lifestyle Considerations throughout the study duration EXCLUSION CRITERIA: 1. Subjects with cardiac pacemakers or other implants that may be affected by or affect the DXA measurements 2. Inadequate access to equipment required for the study (e.g., too little refrigerator storage space or a microwave oven that is too small) as determined by discretion of PI and/or study team 3. Evidence of diseases or conditions that may influence appetite (e.g., cancer, diabetes, alterations of smell or taste post COVID-19), diseases or conditions that affect the immune system, or other conditions at the discretion of the PI and/or study team 4. Taking prescription medications or other drugs that may influence metabolism (including but not limited to diet/weight-loss medication, some psychiatric medications, or other medications at the discretion of the PI and/or study team) 5. People unlikely to adhere to a relatively consistent daily and weekly routine and avoid travel during their participation in the study. For example, people with occupations such as pilots, flight attendants, or frequently travel for work or pleasure. 6. People unlikely to abstain from off study food or supplements that may impact metabolism or appetite at the discretion of the study team 7. Positive pregnancy test or lactating as determined by volunteer report (women only) 8. Inability or unwillingness to use birth control between screening and completion of the study (women only) 9. Symptoms or signs of perimenopause or menopause by volunteer report (women only) 10. Regular vigorous exercise \>150 min per week as determined by volunteer report 11. Alcohol consumption \> 3 drinks per day as determined by volunteer report 12. Regular use of tobacco (smoking, chewing, or vaping), nicotine replacement therapy, or illicit drugs over past 6 months as determined by volunteer report. Subjects may also be excluded based on a urine drug test. 13. Psychological conditions as determined by DSM-5 Self-rated Level 1 Cross-cutting Symptom Measure such as (but not limited to) eating disorders, depression, bipolar disorders, that would be incompatible with safe and successful participation in this study, as determined by investigators 14. Volunteers with strict dietary concerns (e.g. vegetarian or kosher diet, food allergies) or a reported dislike of a significant fraction of the study foods 15. Volunteers unwilling or unable to give informed consent 16. Non-English speakers due to unavailability of required questionnaires in other languages 17. Resting Energy Expenditure test result within 10% of the 2500 calorie requirement at rest
Get updates
Get notified about this study
Sign up to get updates when this study changes or when new studies for Obesity are added.
Genom att skicka in godkänner du våra Användarvillkor
Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
How to take part
Only the study team decides who joins. These are the ways to reach them.
-
The places running it
1 site. The list below names each one and where it is.
-
The official record
ClinicalTrials.gov lists the study team's own contact details, including names and phone numbers. We don't republish those.
-
A doctor treating you
A doctor who knows your case can contact a study site on your behalf, and can tell you whether this study is worth pursuing at all.
Contacts and locations
Locations
-
National Institutes of Health Clinical Center
RECRUITINGBethesda, Maryland, 20892, United States
More trials for these conditions
Other studies related to the condition(s) this trial covers.
- Custom knee guides put to the test in obese patients
- A pill for obesity? early human trial puts MDR-001 to the test
- Can a weekly shot help people who still struggle with weight after bariatric surgery?
- Do GLP-1 Weight-Loss drugs change how teens eat and feel?
- Can electrical muscle stimulation boost exercise benefits after menopause?
- Can a vegan diet shield police officers from heart disease?