Professor Judith Wisnewsky-Aron is not the type of doctor to waver when it comes to medical advice. Faced with her patients, at the Pitié-Salpêtrière hospital in Paris, as with a journalist, this great specialist in overweight, president of the group of specialized obesity centers (CSO), strives to express things in the most direct way possible. It is about his principles, but also about the lives of his patients: treatments are generally better followed if we know what awaits us.
Faced with people who ask her “when” they will be able to stop their treatments against obesity, the famous Ozempic, Wegovy or Mounjaro, the expert, central to questions of care, does not deviate from this rule: “For the moment, the question does not arise. These are not molecules that we can stop”, she explains firmly, even if it means disappointing those who hoped that a few injections would be enough to put them back on the path. slimness.
The statement is certainly abrupt, but necessary. GLP-1 analogues, or “drug treatments for obesity” (OMT), only imitate satiety hormones: under this substance, patients no longer finish their plates and stop snacking. They can lose up to 15 – 20% of their weight, depending on the formulas and molecules, but obesity is not a cure. The way patients store food, their metabolism, continues to malfunction.
70% of the weight returns when stationary
So much so that at the slightest stop of the injections, hunger and fat storage worsen. “Stopping OMT is most often accompanied by a significant weight regain, of the order of two thirds (70%) of the weight lost during the year,” wrote Judith Wisnewsky-Aron on November 25 in a “position paper” of the care centers that she chairs, a document which centralizes the scientific opinion of the members of these structures on treatments.
Several studies, including an analysis of the SURMOUNT-4 clinical trial, published in November 2024 in the scientific journal Jama Internal Medicine also show a deterioration in health indicators. Without GLP-1, cholesterol levels, blood pressure and even blood sugar levels decline. This suggests that “comorbidities”, these associated diseases, skyrocket as soon as treatments stop, and continue to damage the heart, joints and the many other organs affected by overweight diseases.
A step backwards that specialists know too well. This is what happens after each weight loss, and which makes obesity so tough: by eliminating fat, the body also loses lean mass, muscle. Tissues which contribute to the energy consumption of our metabolism, and therefore to keeping us slim. When it loses weight, the body needs less intake to function, and will therefore have a tendency… to store it immediately afterwards.
GLP-1 does not repair
A vicious circle that is so difficult to counter as drug treatments can cause a lot of lean mass to be lost, and do not seem to repair damaged tissues. “We would like these drugs to restore functions linked to eating behavior. Except that today, the data show that this is not the case, there is no definitive reprogramming,” explains Sébastien Czernichow, co-coordinator of the national clinical research network on nutrition (FORCE), head of the nutrition department at the Georges-Pompidou hospital.
Faced with this data, experts agree that GLP-1 should be taken without ever stopping, like many medications for blood pressure or heart problems, for example. “The risk is that a new cycle of loss and recovery will be very poorly experienced and that the situation will deteriorate significantly in the event of a stoppage,” summarizes Jean-Michel Oppert, doctor of nutrition at the Pitié-Salpêtrière hospital. A prescription for life in short, but which already promises to be difficult to maintain: once the light of the fat is lost, the weight stagnates, and with it the morale of the patients.
Injecting yourself – the only way to administer the product at the moment – quickly becomes a chore, in the absence of new encouraging results. As a result, a majority of patients stop in the first year, as shown in particular by a study presented in September 2025, at the annual congress of the European Association for the Study of Diabetes (EASD). After 6 months, 31% of the 77,000 Danish patients monitored for the occasion had put aside their syringes. Figures much higher than during clinical trials.
Important side effects
At issue: the price of drugs, sold there for several hundred euros, without reimbursement, and for several thousand dollars in the United States. In France, the High Authority for Health (HAS) confirmed at the beginning of December the actual benefit of these products, putting them on the path to reimbursement, which could make long-term care easier. Patients still need to resist the side effects. They are not negligible: up to 22% of patients feel nausea, and 17% experience diarrhea or constipation, according to studies.
Faced with this double observation, experts are calling for more independent studies to understand how to mitigate the harmful effects, and to be able to implement appropriate protocols. “We have much less data on weight regain than on the positive effects of the treatment. At the moment, experts are discussing a lot about patient support. Some said that thanks to the drug, we could abandon measures on diet, or physical exercise, I don’t believe that”, indicates Doctor Jean-Michel Oppert.
In the event of stopping, dietary monitoring and appropriate physical activity are important, although limited. “Data from a Danish study show better weight maintenance after weight loss in patients who follow a structured exercise program at the same time as the GLP-1 drug. This shows the importance of lifestyle measures – diet and physical activity – in parallel with treatment,” indicates Jean-Michel Oppert. In an article published in March in the Swiss Medical Review, doctors at the University Hospitals of Geneva also recommend anticipating withdrawal, by reducing the doses little by little. “A gradual reduction (..) could allow the body to adapt more effectively […]” write the experts. The right balance has yet to be found.
.
