Study wrapper · #1148
Early changes in body composition with tirzepatide in adults with obesity: a real-world BIA study.
Angelopoulos N, Rizoulis A, Boniakos A, et al. Nutrition (Burbank, Los Angeles County, Calif.). 2026.
DOI: 10.1016/j.nut.2026.113286PubMed: 42275945
Editor's note
Muscle preservation is the question our readers ask most about the incretin drugs, and this small Greek clinic cohort offers an early real-world answer: roughly four-fifths of weight lost was fat, and the relative share of lean mass actually rose. The caveats matter — 51 people, 12 weeks, no control group, and bioelectrical impedance is a rougher instrument than DEXA. Still, the fat-to-lean ratio here is consistent with what the SURMOUNT trial substudies reported, which lends the finding credibility.
Plain-language abstract
Fifty-one adults with obesity lost an average of 8.2% of body weight over 12 weeks on tirzepatide, and body-composition scans showed about 78% of that loss came from fat rather than muscle.
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