What affects muscle and fat changes after weight-loss surgery
Official title: PILOT STUDY: The Metabolic and Genetic Drivers of Body Composition Changes Following Weight Loss Surgery
Run by The University of Texas Medical Branch, Galveston · NCT07178704 · Data updated 2026-11-12
We will follow people having bariatric surgery to see if differences in behavior, metabolism, or genes explain who loses muscle or regains weight after surgery.
Quick facts
| Study type | Observational |
|---|---|
| Ages | 18 Years to 65 Years |
| Sex | All |
| Enrollment | 100 (estimated) |
| Sponsor | The University of Texas Medical Branch, Galveston Academic / other |
| Locations | 1 site (Galveston, Texas) |
| Status | Recruiting |
| Started | November 4, 2025 |
| Main results expected | February 2027 |
| Study ends | August 2027 |
| Registry record updated | July 10, 2026 |
| Trial ID | NCT07178704 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Ideal candidates are English-speaking adults scheduled for bariatric surgery at UTMB (ages 18–65, BMI 35–50), with a subset of gastric bypass patients aged 30–50 eligible for enhanced metabolic testing and healthy controls aged 30–50 with BMI 20–25 serving as comparisons.
✕Probably not a fit
Patients not having surgery at UTMB, those outside the specified age or BMI ranges, or those unable to complete follow-up visits or English consent procedures are unlikely to benefit from participation.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
This prospective observational project will follow bariatric surgery patients before and for one year after surgery, collecting data on diet, hand-grip strength, and body composition changes (fat and muscle). A group of healthy control volunteers will be recruited for comparison, and a subset of gastric bypass patients aged 30–50 will be invited for detailed metabolic testing of nutrient use. Genetic analyses and behavioral surveys will be combined with metabolic and strength measures to identify factors linked to poor muscle preservation or weight regain. All procedures are conducted at The University of Texas Medical Branch in Galveston and no interventional treatments are administered as part of the protocol.
Why it matters
Potential benefit: If successful, findings could guide personalized perioperative care to protect muscle mass and reduce weight regain after bariatric surgery.
How similar studies have gone: Previous research has repeatedly shown bariatric surgery reduces body weight and can cause muscle loss, but applying combined metabolic and genetic profiling to predict individual muscle loss and weight regain is relatively new and not yet well established.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria (Bariatric Surgery Patients): * Age: 18 to 65 years at time of consent * BMI: 35-65 kg.m-2 * Scheduled to undergo bariatric surgery at UTMB * All races and ethnic backgrounds * Ability to speak and read English * Subject has provided informed consent in a manner approved by the IRB and is willing and able to comply with the trial procedures. Exclusion Criteria (Bariatric Surgery Patients): * Fails the medical criteria for bariatric surgery. * Anemia (hematocrit \< 33 % or donated blood in the past 12 weeks.) * Recent (5 years or less) history of cancer * Systemic steroids or immunosuppressant use for 8 or more consecutive days in the past 6 months, or any use of anabolic steroids or growth hormones in the same period. * Body mass index \< 35 or \> 65 kg.m-2. * Acute infectious disease or chronic infection. * Pregnancy or breast-feeding. * Any medical condition that, in the opinion of the investigator, would place the subject at increased risk for participation. * History of prior non-compliance that would, in the opinion of the investigator, make it difficult for the subject to comply with the study procedures or follow the investigator's instructions. * Concurrent participation in another research study. * Use of an investigational agent in the 30 days prior to signing informed consent.
Where it's running
-
The University of Texas Medical Branch
Galveston, Texas, United States Recruiting
Study contacts
- Principal investigator: Emily J Lantz, PhD — The University of Texas Medical Branch
- Study coordinator: Emily J Lantz, PhD
- Email: ejlantz@utmb.edu
- Phone: 409-772-0643
Similar studies
Other studies for the same condition or treatment. Recruiting studies are listed first.
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TAP (transversus abdominis plane) block before versus after incision for abdominal surgery
This trial tests whether giving a TAP nerve block before the incision instead of after reduces pain and opioid use in adults having elective bariatric or other abdominal surgery.
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Predicting Quality of Life After Bariatric Surgery from Pre-Surgery Profiles
This study tests whether pre-surgical patient traits can predict how quality of life changes after bariatric surgery for adults in the GEROM73 program.
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Interdisciplinary program for identifying and treating disordered eating after weight-loss surgery in Nova Scotia
This program will see if a team-based pathway for screening, diagnosis, and treatment helps adults (19+) who are 3–18 months after weight-loss surgery manage disordered eating.
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.