Fresh analysis suggests that people who discontinue popular GLP-1 drugs like semaglutide or tirzepatide can put back on reduced body mass much more quickly than those who halt traditional diet and exercise plans.
Published data in a prominent medical journal shows that while obese people frequently drop about a fifth of their body weight while on the medication, the weight comes back at an estimated rate of 0.8 kg per month upon discontinuation.
"People buying these drugs need to be cognizant of the risk of rapid weight regain when the therapy ends," cautioned lead investigator Dr. Susan Jebb.
That rate of regain suggests a reversion to starting weight in about one and a half years.
Comparing Treatments
The study, which reviewed 37 of studies involving over 9,000 of participants, contrasted the outcomes of GLP-1 agonists with older methods.
The team emphasize that individuals who shed pounds through lifestyle changes alone usually have a slower creep back—perhaps 0.1 kg a month—after stopping.
Explaining the Rapid Rebound
Nutrition scientists propose the mode of action of the drugs explains the amplified weight return.
These medications imitate a body's own chemical called GLP-1, which controls hunger.
"Artificially providing the hormone levels far above than normal could lead to the system to produce less of its endogenous hormone, and may also lessen responsiveness to its effects," explained Dr. Adam Collins, a nutrition expert.
"Withdrawal of this GLP-1 'fix' means appetite is unsuppressed, making excessive eating a significant risk."
An Ongoing Issue?
The NHS suggest the injections for individuals with obesity-related medical conditions, alongside recommended lifestyle changes.
A number of clinicians argue that, due to the significant potential of weight regain, the therapy might need to be ongoing.
This opinion is reinforced by drug manufacturers, who note that the results "underscore the persistent character of obesity," comparing it to managing diseases like high blood pressure.
Patient Experiences
People who have discontinued the jabs describe a sudden return of cravings.
"It was like a switch that goes on and I was suddenly ravenous," said a patient.
This challenge is worsened if individuals have not established lasting lifestyle or habit changes during therapy.
Widespread Adoption
Figures suggest that millions of adults in the UK have used these injections in the past year, with demand remaining high.
- Adoption is greater among women than males.
- The middle-aged age group shows the greatest level of interest.
- A large proportion obtain the medications through private healthcare rather than the NHS.
Ultimately, experts caution that while these medications are powerful agents for weight loss, they are not a permanent cure and maintained weight loss hinges on combined lifestyle management.
