UC San Diego Health is running a 260-person, year-long trial with Oura to find out whether patients lose more weight when their obesity care team can see their ring’s sleep, heart rate and activity data.
- The trial is called SMART-BMI and is listed on ClinicalTrials.gov as NCT07736729, with Oura Health as a collaborator.
- It enrols two groups of adults in parallel: people having bariatric surgery and people starting GLP-1 or dual GLP-1/GIP medication.
- Participants wear an Oura Ring 4, and their dietitians, nurses and doctors view the data on a dashboard during routine care.
- In the second phase, patients are randomised so that only one group’s care team and coach see the ring data, while both groups get the same amount of coaching.
- The main measure is percentage body weight lost after 52 weeks, with blood sugar (HbA1c), blood pressure, cholesterol, quality of life and whether GLP-1 patients stay on their medication as secondary measures.
- The registry estimates the main results will be complete at the end of 2030.
What it means for us
The trial measures what happens when a care team acts on the ring data. The study record says earlier trials that simply handed out wearables, with nobody acting on the data, generally did not improve weight loss.
No results exist yet. If care teams acting on Oura data do get better outcomes, that would be clinical evidence for the sleep and recovery tracking that recovery trackers already sell to those interested in wellness and general fitness.
Quick answers
Can I join the Oura obesity trial?
Only adults aged 18 to 64 who are being treated at UC San Diego Health’s bariatric or obesity medicine clinics can take part. They must have a BMI of 27 or more, or qualify for bariatric surgery.
Which Oura Ring does the trial use?
The trial record names the Oura Ring Generation 4, worn continuously for 52 weeks alongside normal surgical or medication treatment.
Related: Oura Ring 5 and Ring 4 compared, Oura adds Cardio Effort and automatic VO2 max and best fitness tracker.
Last Updated on 28 October 2026 by tfk the5krunner
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- Oura Ring 5: My partner’s recovery tracker of choice.
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tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors. See the gear tfk uses. ID
