People regaining weight after stopping new weight-loss drugs do so four times faster than those who discontinue diet and exercise plans, according to research released Thursday.
Rapid Regain: Why Weight Loss Drugs Aren’t a Quick Fix
A new study reveals a concerning trend: weight bounces back quickly when medication is stopped.
- Individuals on GLP-1 agonists can lose 15-20% of their body weight.
- Weight regain occurs at approximately 0.4 kilograms per month after stopping medication.
- Participants regained an average of 10 kilograms within a year of ceasing treatment.
- Long-term success likely requires ongoing medication or combined approaches.
The latest generation of injectable, appetite-suppressing drugs, known as GLP-1 agonists, has dramatically altered the landscape of obesity and diabetes treatment in recent years. These medications have demonstrated the ability to help individuals shed between 15 and 20 percent of their body weight. But what happens when the injections stop?
“This all appears to be a good news story,” said Susan Jebb, a public health nutrition scientist at Oxford University and co-author of a new BMJ study. However, she noted that “around half of people discontinue these medications within a year,” during a press conference.
Discontinuation can be attributed to factors like common side effects, such as nausea, or the substantial cost—these drugs can exceed $1,000 per month in the United States.
Researchers reviewed 37 studies examining cessation of various weight-loss drugs and found that participants regained around 0.4 kilograms (approximately 0.9 pounds) each month. Six clinical trials specifically focused on semaglutide—the active ingredient in Novo Nordisk’s Ozempic and Wegovy—and tirzepatide, used in Eli Lilly’s Mounjaro and Zepbound.
Trial participants taking these two drugs experienced an average weight loss of nearly 15 kilograms. However, after stopping medication, they regained 10 kilograms within a year, the longest follow-up period available for these relatively new drugs. The researchers project that participants would return to their original weight within 18 months.
What happens to overall health when the weight returns? Measurements of heart health, including blood pressure and cholesterol levels, also reverted to baseline levels after 1.4 years.
Interestingly, individuals following diet and exercise programs—without medication—lost significantly less weight initially. However, it took them an average of four years to regain any lost kilos, meaning those taking drugs regained weight four times faster.
‘Starting Point, Not a Cure’
“Greater weight loss tends to result in faster weight regain,” explained Sam West, lead study author from Oxford University. However, further analysis revealed that weight gain was “consistently faster after medication, regardless of the amount of weight lost in the first place,” he added.
This could be because individuals who adopt healthier eating habits and exercise routines are more likely to maintain those behaviors even as they regain some weight.
Jebb emphasized that GLP-1 drugs “are a really valuable tool in obesity treatment—but obesity is a chronic relapsing condition.” She added, “One would expect that these treatments need to be continued for life, just in the same way as blood pressure medication.”
The researchers stressed that this potential need for lifelong treatment would significantly impact how national health systems assess the cost-effectiveness of these drugs.
“This new data makes it clear they are a starting point, not a cure,” said Garron Dodd, a metabolic neuroscience researcher at the University of Melbourne who was not involved in the study. “Sustainable treatment will likely require combination approaches, longer-term strategies, and therapies that reshape how the brain interprets energy balance, not just how much people eat.”
Publication details
Weight regain after cessation of medication for weight management: systematic review and meta-analysis, The BMJ (2026). DOI: 10.1136/bmj-2025-085304
Journal information:
British Medical Journal (BMJ)
Clinical categories
© 2026 AFP
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Study shows how fast kilos return after ending weight-loss drugs (2026, January 11)
retrieved 11 January 2026
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