Fresh analysis suggests that patients who discontinue blockbuster weight-loss injections like Mounjaro or Wegovy may regain lost weight far faster than those who end traditional diet and exercise programs.
Published data in a prominent medical journal demonstrates that while obese individuals often shed substantial amounts of their body weight while on the medication, the weight comes back at an estimated rate of 0.8 kg per month once they quit.
"Individuals using these treatments should be informed of the risk of rapid rebound weight gain when the medication concludes," stated expert Dr. Susan Jebb.
That rate of recovery suggests a return to pre-treatment weight in about one and a half years.
Weighing Treatments
The analysis, which reviewed dozens of trials involving over 9,000 of participants, compared the outcomes of these new drugs with conventional dieting.
Researchers note that people who lose weight through diet and exercise typically see a slower weight regain—around 100 grams monthly—once they finish.
Explaining the Fast Regain
Nutrition scientists believe the mode of action of the injections is key to understanding the amplified regain.
GLP-1 drugs copy a body's own chemical called glucagon-like peptide-1, which moderates feelings of fullness.
"Long-term administration of GLP-1 concentrations far above than normal might result in the system to produce less of its endogenous GLP-1, and may also diminish responsiveness to its effects," said Dr. Adam Collins, a dietetics expert.
"Withdrawal of this GLP-1 'fix' leads to appetite is uncontrolled, making excessive eating a significant risk."
A Lifelong Issue?
Medical guidelines advise the injections for individuals with weight-linked health risks, alongside prescribed diet and exercise modifications.
A number of clinicians contend that, given the likelihood of relapse, the therapy might need to be ongoing.
This perspective is supported by drug manufacturers, who say that the results "highlight the long-term nature of obesity," akin to managing diseases like high blood pressure.
Patient Experiences
People who have discontinued the medication describe a sudden return of hunger.
"I experienced something activating and you're instantly extremely hungry," described a patient.
The struggle is worsened if individuals have not developed permanent dietary or behavioural changes during therapy.
Widespread Adoption
Survey data indicate that millions of adults in the UK have tried these injections in the past year, with demand continuing to grow.
- Adoption is higher among females than males.
- The 40s and 50s demographic shows the greatest usage rates.
- Many access the drugs through private healthcare rather than the NHS.
Ultimately, clinicians emphasize that while GLP-1 drugs are effective agents for weight loss, they are not a permanent solution and long-term success likely depends on integrated behavioural support.
