A comprehensive analysis by the University of Oxford's Biomedical Research Centre has revealed that patients who discontinue GLP-1 weight loss medications typically regain all lost weight within two years, with newer drugs showing both greater initial weight loss and faster subsequent weight regain.
The study, presented at the European Congress on Obesity, analyzed 11 studies encompassing 7,944 titles and abstracts to examine weight regain patterns after stopping GLP-1 receptor agonists. The research compared older medications like Byetta and Victoza with newer formulations including Ozempic/Wegovy and Mounjaro.
Rapid Weight Regain Across All GLP-1 Medications
The analysis found that patients using any GLP-1 medication lost an average of 7.9 kg (17.4 lbs) during treatment. However, after discontinuation, participants regained weight at a monthly rate of 0.7 kg (1.5 lbs), projecting a return to original weight within just under one year.
"These drugs are very effective at helping you lose weight, but when you stop them, weight regain is much faster than [after stopping] diets," said Susan Jebb, co-author of the study and professor of diet and population health at University of Oxford.
Newer Drugs Show Enhanced Efficacy but Accelerated Regain
Patients taking newer GLP-1 medications demonstrated significantly greater weight loss, averaging 16.1 kg (35.5 lbs) compared to older formulations. However, this enhanced efficacy came with a trade-off: weight regain occurred at a slightly faster rate of 0.8 kg (1.8 lbs) per month after stopping treatment.
The study specifically noted that patients using semaglutide (Wegovy) and tirzepatide (Mounjaro) "lost double the amount of weight compared with people using older jabs – 16kg on average – patients put on 9.6kg within a year, meaning they could expect to regain all 16kg again in just over 20 months."
Implications for Treatment Duration and Approach
The findings challenge current treatment guidelines established by the National Institute for Health and Care Excellence, which recommend GLP-1 medications for two years or less. The research suggests this timeframe may be insufficient for maintaining weight loss benefits.
"Either people really have to accept this as a treatment for life, or we in science need to think really, really hard, how to support people when they stop the drug," Jebb stated.
The study concluded that "this rate of regain is greater than observed following behavioural weight management programmes and sounds a cautionary note to the use of these medications without a more comprehensive approach to the treatment of obesity and prevention of weight regain."
Lifestyle Factors Remain Critical
Tam Fry, chair of the National Obesity Forum, emphasized that the results shouldn't surprise anyone. "It shouldn't surprise anyone if people regain weight having used GLP-1 drugs without seriously attempting to improve their lifestyle... Using GLP-1 is not the quick fix which many users believe it to be," Fry told media outlets.
The researchers noted that the difference in weight regain speed between medication cessation and diet cessation might stem from the fundamental nature of these interventions. While dieting requires ongoing self-control and behavioral changes, GLP-1 medications primarily suppress hunger without teaching sustainable lifestyle modifications.
The study underscores the importance of combining pharmacological interventions with comprehensive lifestyle modifications, including dietary changes, exercise, stress management, and behavioral support, to achieve lasting weight management success.
