The claimEvidence A · guideline-tier
Ozempic is a side-effect-free weight-loss miracle
The evidence
STEP 1 extension (Wilding 2022): ~2/3 of weight is regained within a year of stopping — effectively lifelong therapy. ~70% have GI side effects and lean-mass loss is elevated.
The mechanism, in brief
GLP-1 (glucagon-like peptide-1) is a gut hormone, not a synthetic invention. Secreted by intestinal L-cells (mainly distal ileum + colon) after meals; its native half-life is only 1-2 minutes (rapidly degraded by DPP-4 enzyme).
Sources (2)
- Wilding, J. P. H., Batterham, R. L., Calanna, S., Davies, M., Van Gaal, L. F., Lingvay, I., et al. (2021). Once-weekly semaglutide in adults with overweight or obesity (STEP-1). New England Journal of Medicine, 384(11), 989-1002.
- Jastreboff, A. M., Aronne, L. J., Ahmad, N. N., Wharton, S., Connery, L., Alves, B., Kiyosue, A., Zhang, S., Liu, B., Bunck, M. C., & Stefanski, A. (2022). Tirzepatide once weekly for the treatment of obesity. The New England Journal of Medicine, 387(3), 205–216.