People who stop taking weight loss jabs regain all the weight originally lost in under two years, significantly faster than those on any other weight loss plan, according to a landmark study published in the BMJ. The analysis, led by academics at the University of Oxford, reviewed 37 studies involving 9,341 participants and found that weight was regained at a rate of 0.4kg per month after stopping medication, with participants returning to their original weight within an average of 1.7 years.
The study found that people on weight loss medications lost an average of 8.3kg during treatment but regained 4.8kg within the first year. The rate of weight regain was almost four times faster compared with behavioural programmes, regardless of the amount of weight lost during treatment. Dr Sam West of the University of Oxford said the rapid regain was not due to the medication itself but reflected the nature of obesity as a chronic, relapsing condition.
Benefits on cardio-metabolic health markers, such as blood pressure and cholesterol, also returned to their original level within 1.4 years of stopping treatment. The medications, known as GLP-1 agonists, were originally developed for diabetes and work by mimicking the hormone that helps people feel full.
Dr Faye Riley of Diabetes UK said the research reinforces that these drugs are not a quick fix and need to be prescribed with tailored wraparound support. Katharine Jenner of the Obesity Health Alliance added that regaining weight reflects the reality of living in a food environment that pushes people towards unhealthy options. An NHS spokesperson said the drugs must be paired with behavioural and lifestyle support to keep the weight off long term.
