Time windows
“Around 30 days” uses a weight logged between days 15 and 44; 60 days uses days 45–74; 90 days uses days 75–105. Missing values are never filled in.
The Zelta Study · ongoing
About the study, and what it can’t tell you.
We want you to be able to judge these results for yourself. This page explains how the study was done, how to read the numbers, and where its limits are.
- Type
- Retrospective review of Zelta records
- Data frozen
- 7 October 2026
- Status
- Ongoing; clinical review in progress
- Patients with repeat weights
- 96
What the study is
The Zelta Study looks back at the records of patients in Zelta care: weight logs, recorded medicines and doses, screening answers, care records and uploaded blood reports. The data was frozen on 7 October 2026 and analysed without any patient identities.
It is ongoing. Clinical review of the records and data extraction are still being completed, and we’ll update the results as more patients reach later milestones. The current version covers weight and 34 blood markers.
It is not a clinical trial. Nobody was assigned a treatment for the study, and there is no untreated comparison group.
How to read the numbers
Each result has its own group
Every window, medicine, factor and blood marker has its own patients, so counts differ and shouldn’t be added together.
Ranges
Shaded ranges are 95% intervals. When a range includes zero, we can’t be confident there was any change.
Limitations
- 01
It can’t prove cause and effect
This is a look back at our own records, not a randomised trial. There is no untreated comparison group, so we can’t say how much of the change came from treatment.
- 02
It isn’t a medicine comparison
People on semaglutide and Mounjaro started at different weights and doses. The results describe each group; they don’t show which medicine is better.
- 03
Only people who kept logging
Each result includes people with a before-and-after measurement. People who stopped logging may have done differently.
- 04
Small groups at later points
Only 9 patients had reached 90 days, and each blood marker comes from 5–11 patients. These numbers will change as the study grows.
What’s next
We’ll complete the clinical review, add patients as they reach the 60- and 90-day points, and publish updated results with a new version date. More consistent weight logging will let the next version answer questions this one can’t.
For the full analysis, including treatment-start timing, every subgroup and the plotted data, see the technical report. For questions about your own care, talk to your Zelta doctor.
Back to the results