Fresh analysis suggests that individuals who come off blockbuster GLP-1 drugs like semaglutide or tirzepatide may regain reduced body mass at a significantly accelerated pace than those who halt conventional diet and exercise regimens.
Research printed in a leading medical journal demonstrates that while overweight individuals often shed a large proportion of their total mass while undergoing treatment, the mass returns at an average rate of nearly a kilo each month once they quit.
"Users using such drugs need to be informed of the potential of rapid rebound weight gain when the treatment ends," cautioned researcher Dr. Susan Jebb.
This pace of regain implies a reversion to starting weight within about 18 months.
Weighing Therapies
The analysis, which reviewed 37 of studies involving over 9,000 of participants, contrasted the results of the injectable medications with older methods.
The team emphasize that individuals who shed pounds through dieting typically experience a less rapid creep back—approximately 0.1 kg a month—post-intervention.
Understanding the Rapid Regain
Experts propose the mode of action of the drugs is key to understanding the amplified rebound.
GLP-1 drugs imitate a natural hormone called glucagon-like peptide-1, which moderates feelings of fullness.
"Artificially providing the hormone concentrations far above than normal might result in the system to generate a reduced amount of its own natural GLP-1, and may also diminish sensitivity to its effects," said Dr. Adam Collins, a dietetics researcher.
"Stopping of this hormone supplement means hunger is unsuppressed, making overeating far more likely."
A Lifelong Disease?
The NHS recommend the injections for individuals with obesity-related health risks, alongside prescribed diet and exercise modifications.
A number of clinicians argue that, due to the likelihood of weight regain, the treatment should be considered ongoing.
This view is echoed by drug manufacturers, who say that the results "highlight the chronic nature of excess weight," comparing it to managing diseases like hypertension.
Patient Testimonies
People who have come off the jabs describe a sudden return of hunger.
"It felt as if something activating and I was suddenly starving," recalled an individual.
This challenge is compounded if patients have not established permanent lifestyle or habit changes during treatment.
Widespread Use
Survey data show that a significant number of people in the UK have tried these injections in the last 12 months, with demand being substantial.
- Adoption is more common among females compared to men.
- The middle-aged age group shows the highest level of interest.
- A large proportion obtain the medications through private prescriptions rather than public health services.
Ultimately, experts caution that while GLP-1 drugs are effective tools for weight loss, they are not a standalone cure and long-term success likely depends on ongoing lifestyle changes.
