Fresh analysis reveals that people who discontinue new GLP-1 drugs like Mounjaro or Wegovy can put back on reduced body mass much more quickly than those who end conventional diet and exercise programs.
Published data in a major medical journal shows that while obese individuals frequently drop a large proportion of their body weight while undergoing treatment, the mass is regained at an estimated rate of 0.8 kg per month after stopping.
"People purchasing these treatments must be aware of the danger of quick rebound weight gain when the therapy is stopped," warns lead investigator Dr. Susan Jebb.
This pace of regain implies a reversion to starting weight in about 18 months.
Comparing Therapies
The analysis, which reviewed dozens of trials involving thousands of participants, compared the effects of GLP-1 agonists with conventional dieting.
Scientists point out that people who shed pounds through diet and exercise generally see a more gradual creep back—perhaps 0.1 kg a month—once they finish.
Understanding the Rapid Rebound
Nutrition scientists believe the mechanism of the jabs is key to understanding the amplified regain.
GLP-1 drugs imitate a body's own chemical called GLP-1, which moderates appetite.
"Artificially providing GLP-1 levels several times higher than the body's typical production might result in the system to generate a reduced amount of its own natural GLP-1, and may also reduce sensitivity to its actions," said Dr. Adam Collins, a dietetics expert.
"Withdrawal of this hormone supplement results in hunger is unsuppressed, making excessive eating far more likely."
A Chronic Issue?
The NHS recommend the jabs for individuals with obesity-related medical conditions, alongside recommended lifestyle changes.
Professionals contend that, considering the likelihood of relapse, the therapy is often life-long.
This perspective is supported by pharmaceutical companies, who state that the results "highlight the chronic nature of excess weight," similar to managing conditions like high blood pressure.
Patient Accounts
Users who have discontinued the medication describe a powerful return of hunger.
"It felt as if a switch that goes on and you become starving," described one woman.
The struggle is worsened if patients have not developed lasting lifestyle or habit changes during therapy.
Significant Use
Survey data show that millions of adults in the UK have used these injections in the past year, with demand continuing to grow.
- Use is higher among women compared to males.
- The middle-aged demographic shows the greatest level of interest.
- A large proportion obtain the drugs through private prescriptions rather than the NHS.
Finally, clinicians caution that while GLP-1 drugs are powerful tools for shedding pounds, they are not a standalone fix and lasting health benefits relies on ongoing behavioural management.
