A large-scale meta-analysis of previous studies has found that the benefits gained in weight loss and other health indicators by obese or overweight patients typically disappear within two years once they stop taking weight-loss medications.

Researchers analyzed data from 9,341 obese or overweight patients across 37 studies who had used 18 different weight-loss drugs. The results showed that after discontinuation, patients regained an average of nearly 1 pound (approx. 0.4 kg) per month. It is estimated that patients return to their pre-treatment weight levels within 1.7 years.

“Effect Zeroed Out” in Less Than Two Years

The study, published in The BMJ (British Medical Journal), indicates that as medication is stopped, cardiovascular risk factors improved by the treatment—including blood pressure and cholesterol levels—return to pre-treatment levels within an average of 1.4 years. Essentially, the clinical benefits are “zeroed out” in less than two years.

Among all subjects, approximately half had used GLP-1 receptor agonists. This included 1,776 individuals treated with the newest generation of more potent drugs: Semaglutide (marketed as Ozempic and Wegovy) by Novo Nordisk (NVO), and Tirzepatide (marketed as Mounjaro and Zepbound) by Eli Lilly (LLY).

A Structural Shift in Obesity Treatment

For a long time, weight loss achieved through diet and physical activity was considered the cornerstone of obesity treatment. However, the advent of GLP-1 drugs is driving a profound structural transformation. These new medications can help patients lose 15%–20% of their baseline weight within a year while simultaneously improving cardiometabolic markers such as blood sugar, blood pressure, and lipids. They have even shown positive signals in treating fatty liver disease, sleep apnea, and reducing the incidence of cardiovascular events.

The study found that weight regain was faster among patients using Semaglutide or Tirzepatide, with an average increase of approximately 1.8 pounds (0.8 kg) per month post-discontinuation.

However, Dimitrios Koutoukidis, the lead researcher from the University of Oxford and senior author of the study, noted: “Because Semaglutide and Tirzepatide produce much larger initial weight loss, these patients ultimately reach the point of returning to baseline weight at roughly the same time as users of other weight-loss drugs.” Specifically, the return to baseline for the new generation of GLP-1 drugs is about 1.5 years, compared to the 1.7-year average for all weight-loss drugs combined.

Biological Dependence and Long-term Management

The research also discovered that regardless of how much weight was initially lost, the monthly rate of regain after stopping medication was generally faster than that seen in weight management programs relying solely on behavioral interventions (such as diet and exercise). This suggests that pharmacological weight loss is physiologically more dependent on continuous intervention; once interrupted, the body’s strong compensatory mechanisms rapidly kick in.

As this was a retrospective analysis, researchers could not determine which specific patients were more likely to successfully maintain their weight after stopping the drugs. “Figuring out ‘who can maintain weight loss and who cannot’ is almost the Holy Grail of obesity research, but no one has a definitive answer yet,” Koutoukidis said.

Investment and Industry Perspective

From an industry and capital markets perspective, this research reinforces an increasingly clear conclusion: GLP-1 weight-loss drugs are “chronic long-term management tools” rather than one-time treatments. Rather than diminishing the revolutionary value of GLP-1 drugs, the study validates their product attributes of high user “stickiness” and sustained long-term demand from a long-term perspective.