Overview
- The Oxford systematic review, published in the BMJ, analyzed 37 trials with 9,341 adults who received weight-loss drugs for about 39 weeks and were followed for roughly 32 weeks, achieving on-treatment losses near 20% of body weight.
- After discontinuation, participants regained about 0.4 kg per month overall and around 0.8 kg per month after newer GLP‑1 agents, which the authors estimate would restore baseline weight in roughly 18 months.
- Weight returned substantially faster than after ending behavioral programs, with a rebound rate about four times higher and an average 0.3 kg per month faster regain.
- Cardiometabolic gains during therapy largely waned after stopping, with blood pressure, cholesterol, and glucose measures returning to baseline within approximately 1.4 to 2 years.
- Roughly half of patients stop treatment within a year due to side effects and cost, many use these drugs without medical or behavioral support (about 90%), and experts urge sustained, supervised care or ongoing therapy when tolerated.