Ketogenic versus low-fat diets to help keep weight off and change energy use and appetite
Official title: Ketogenic Diets for Weight Loss Maintenance: Impact on Energy Expenditure and Appetite in Individuals With Obesity
Run by University of Alabama at Birmingham · NCT06736028 · Data updated 2026-11-12
This tests whether a ketogenic diet versus an isocaloric low-fat diet helps people with obesity keep weight off by increasing daily energy use and reducing appetite.
Quick facts
| Study type | Interventional |
|---|---|
| Ages | 18 Years to 65 Years |
| Sex | All |
| Enrollment | 20 (estimated) |
| Sponsor | University of Alabama at Birmingham Academic / other |
| Locations | 1 site (Birmingham, Alabama) |
| Status | Recruiting |
| Started | August 1, 2025 |
| Main results expected | December 31, 2026 |
| Study ends | March 30, 2027 |
| Registry record updated | April 7, 2026 |
| Trial ID | NCT06736028 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Adults aged 18–65 with BMI 30–45 who can lose at least 5% body weight during a 4-week low-energy diet, are not pregnant or lactating, and do not have medical conditions or medications that affect metabolism.
✕Probably not a fit
People with diabetes, prior bariatric surgery, untreated thyroid disease, certain inflammatory or organ diseases, pregnant or breastfeeding people, or those taking weight-affecting medications are excluded and would not be expected to benefit from this protocol.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
Adults with obesity first complete a 4-week low-energy diet aiming for at least 5% weight loss. Those who achieve the target are randomized 1:1 to six weeks of weight-loss maintenance on either a ketogenic diet or an isocaloric low-fat diet, with the first two weeks as gradual refeeding. Total energy expenditure and measures of appetite are collected during the maintenance phase to determine metabolic and hunger effects of the diets. The intervention duration is 10 weeks and includes behavioral support and calorie guidance.
Why it matters
Potential benefit: If successful, the approach could help people maintain weight loss by increasing daily energy expenditure and reducing appetite, making long-term weight control easier.
How similar studies have gone: Some prior trials show ketogenic diets produce faster early weight loss and can reduce appetite, but clear evidence that ketogenic diets increase total energy expenditure during weight-loss maintenance is limited.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: * BMI 30-45 kg/m2 * Both men and women * Age between 18-65 years * Sedentary to moderately active (\<2 h/wk of moderate, structured, intentional, exercise) Exclusion Criteria: * Pregnancy or lactation * Daily use of tobacco (\>1 pk/wk) * Change in weight greater than 5 lb in the previous 3 months * Cognitive impairment * Previous bariatric surgery * History of eating disorder * Presence of any condition (e.g. DM2, PCOS, inflammatory disease, untreated thyroid disease, fluid overload states such as chronic kidney disease, congestive heart failure, or cirrhosis) * Use of any medication (e.g., glucocorticoid, GLP-1 analogues, hormone replacement therapy) deemed to interfere with study outcomes. * Pre-menopausal women will need to have a regular menstrual cycle (28+/-2 days) or be on hormonal contraceptives * Fasting glucose plasma concentration \>125 mg/dl and/or HbA1c \> 6.4%
Where it's running
-
University of Alabama at Birmingham
Birmingham, Alabama, United States Recruiting
Study contacts
- Study coordinator: Catia Martins, PhD
- Email: catia197@uab.edu
- Phone: 205-934-7922
Similar studies
Other studies for the same condition or treatment. Recruiting studies are listed first.
-
Ocular Changes in People Using Tirzepatide or Semaglutide
This study checks whether eye structure and blood vessels change in adults with obesity who are taking semaglutide or tirzepatide as part of routine care.
-
Whole-Body Vibration Training in Women With Obesity With and Without Type 2 Diabetes
This study tests whether eight weeks of supervised whole-body vibration training changes ankle muscle activity and walking performance in women with obesity, comparing those with and without type 2 diabetes.
-
Berobenatide for knee pain in adults who are overweight or with obesity
This study tests berobenatide vs. placebo to see if it reduces knee pain and improves function while helping with weight in adults with knee osteoarthritis and overweight/obesity.
-
Weekly berobenatide for knee osteoarthritis in adults who are overweight or obese
This study tests whether weekly berobenatide helps reduce knee pain and improve function, while also affecting body weight, in adults with knee osteoarthritis who are overweight or obese (with or without type 2 diabetes).
-
Maridebart cafraglutide in people who switched from weekly GLP-1 receptor agonists
This study tests how much maridebart cafraglutide appears in the blood after people with overweight or obesity switch from weekly GLP-1 receptor agonists.
-
EloraTZP for weight loss in adults with overweight/obesity and type 2 diabetes
This trial tests whether a coformulation of eloralintide and tirzepatide helps people with obesity or overweight and type 2 diabetes lose weight compared with tirzepatide alone.
How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.