People who stop taking popular weight loss drugs like Wegovy and Mounjaro regain their lost weight almost four times faster than traditional dieters, according to a major study by University of Oxford researchers. The findings highlight a critical challenge as millions turn to these medications: keeping the weight off after treatment ends.
The study, published in the British Medical Journal, analyzed 37 studies involving over 9,000 people. Those using Wegovy and Mounjaro lost just under 15kg on average during treatment, but regained 10kg within the first year of stopping. Projections suggest all weight returns within 1.5 years.
Susan Jebb, professor of diet and population health at the University of Oxford and adviser to ministers and the NHS on obesity, said: «In summary, what we've shown in this particular piece of analysis is that weight regain after medication is common and is rapid.»
The health benefits vanish alongside the pounds. Blood sugar levels, cholesterol, and blood pressure improvements all return to baseline within 1.4 years of stopping medication. «The cardiometabolic benefits essentially parallel weight – and so as weight is regained, the cardiometabolic benefits are lost,» Jebb explained.
Why Weight Returns So Rapidly
The speed of regain sets these drugs apart from behavioral weight loss programs. Traditional dieters keep weight off for just under four years on average, while medication users regain it in under two years.
Dr Adam Collins, associate professor of nutrition at the University of Surrey, offered a biological explanation: «Artificially providing GLP-1 levels several times higher than normal over a long period may cause you to produce less of your own natural GLP-1, and may also make you less sensitive to its effects. [...] As soon as you withdraw this GLP-1 'fix', appetite is no longer kept in check, and overeating is far more likely.»
Studies suggest half of people stop their weight loss medication, whether due to inability to afford private prescriptions, side effects, or reaching their goal weight. The NHS limits Wegovy prescriptions to two years maximum, while Mounjaro has no limit.
Expert Solutions and Strategies
Obesity specialists Dr. James Hill and Dr. Holly Wyatt have published a book titled "Losing The Weight Loss Meds," offering a ten-week strategy to prevent weight regain. The approach focuses on stabilizing appetite with protein and fiber-rich meals, using movement to support metabolism through about 30 minutes of moderate activity most days, planning stress responses without resorting to food, and actively shaping one's environment to support goals.
Jebb emphasized the need for long-term thinking: «Obesity is a chronic relapsing condition, and I think one would expect that these treatments need to be continued for life, just in the same way as blood pressure medication.» She warned those paying privately to «need to be aware of the very high risk of rapid weight regain when treatment ends» and be «aware of the financial consequences.»
Separate research from University College London and University of Cambridge highlighted additional risks. Dr Marie Spreckley from Cambridge noted: «Many people receive little or no structured guidance on diet quality, protein intake, or micronutrient adequacy while experiencing marked appetite suppression. [...] If nutritional care is not integrated alongside treatment, there's a risk of replacing one set of health problems with another, through preventable nutritional deficiencies and largely avoidable loss of muscle mass.»
An NHS spokesman responded that the treatments «are not a magic fix and must be paired with behavioural and lifestyle wraparound support including advice on healthier diets and physical activity to keep the weight off in the long term.» The NHS Digital Weight Management Programme will expand to 125,000 more people per year as part of a ten-year health plan.
The Oxford researchers concluded in their paper: «As obesity is a chronic and relapsing condition, prolonged treatment with weight management medications may be required to sustain the health benefits. [...] Further research is needed to study how to support people to use these drugs effectively, either through prolonged adherence or, possibly, through intermittent periods of treatment.»
Note: This article was created with Artificial Intelligence (AI).
