A review published in the British Medical Journal indicates that individuals using weight-loss medication may regain lost weight up to four times faster than those who lose weight through conventional diet.
The data indicates that individuals can lose around one-fifth of their body weight, but often regain it quickly once treatment stops. On average, patients regain about 0.8 kilograms per month, returning to their pre-treatment weight within roughly 18 months, according to the review.
The findings were drawn from 37 clinical trials involving more than 9,000 participants, comparing the effects of weight-loss injections with conventional dieting or other pharmacological approaches. By contrast, the review notes that individuals who lose weight through dietary changes alone tend to regain weight more slowly, on average around 0.1 kilograms per month, although rates vary between individuals.
Only eight of the studies evaluated newer GLP-1 drugs, including semaglutide and tirzepatide, with follow-up periods limited to one year after discontinuation.
The researchers commented, “This evidence cautions against short term use of weight management medications, emphasises the need for further research into cost effective strategies for long term weight control and reinforces the importance of primary prevention.”