What percentage of fat mass was lost?
DXA scans measured body composition. The substudy enrolled 189 adults with type 2 diabetes and BMI 25–50; 103 completed treatment with scans at baseline and week 36.
| Study arm | Fat-mass reduction |
|---|---|
| Retatrutide 0.5 mg | 4.9% |
| Retatrutide 4 mg (pooled) | 15.2% |
| Retatrutide 8 mg (pooled) | 26.1% |
| Retatrutide 12 mg | 23.2% |
| Dulaglutide 1.5 mg | 2.6% |
| Placebo | 4.5% |
Sources: Body composition changes during treatment with retatrutide in adults with type 2 diabetes
Fat mass versus body-fat percentage: what is the difference?
If someone hypothetically started with 40 kg of fat, a 26.1% reduction would be 10.44 kg of fat. Body-fat percentage instead divides fat mass by total body mass. The measures are not interchangeable; this arithmetic example is not a forecast.
Did Retatrutide preserve all lean mass?
No. Lean mass also fell; its share of weight loss was similar to other obesity treatments. Gastrointestinal events were frequent. The small substudy and incomplete follow-up limit interpretation, and the different population prevents direct comparison with the obesity trial. Lilly funded the study; authors disclosed employment and shareholdings.
Sources: Body composition changes during treatment with retatrutide in adults with type 2 diabetes
Sources and further reading
This guide summarises selected sources. Original publications contain the full methods, results and disclosures; the selection is not a systematic review.
- Body composition changes during treatment with retatrutide in adults with type 2 diabetes (external)
Coskun et al. The Lancet Diabetes & Endocrinology (2025), 13:674–684. DOI: 10.1016/S2213-8587(25)00092-0. Phase 2 DXA substudy.
Continue exploring
- Retatrutide weight loss: 48-week trial results
- Retatrutide and liver fat: MRI trial results explained
- Retatrutide research: trials, outcomes and limitations
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