An estimated 1.6 million adults in England, Wales and Scotland used prescription weight loss drugs such as Wegovy and Mounjaro between early 2024 and early 2025, according to new research led by University College London. The study, published in BMC Medicine and funded by Cancer Research UK, also found substantial unmet demand, with a further 3.3 million people saying they would consider using weight loss medication over the next year.
Researchers analysed survey responses from 5,260 adults who were representative of the general population and who took part in early 2025. Overall, 4.5% reported using one of the medications in the past year for any reason, while 2.9% said they used them specifically for weight loss, equating to around 1.6 million people. A smaller group—1.7%, or roughly 910,000 adults—reported using the drugs exclusively for weight loss, without another reason such as managing type 2 diabetes or reducing cardiovascular risk.
Use of weight loss medication was not evenly distributed across the population. The researchers found it was about twice as common among women as men and most prevalent among those aged 45 to 55. Higher use was also reported by people who experienced moderate or severe psychological distress in the month before the survey. While overall usage rates were similar across social grades, interest in future use was notably higher among more disadvantaged groups, where obesity rates tend to be greater, suggesting that private prescribing may not be meeting demand.
Taken together, the findings suggest that nearly 4.9 million adults in Great Britain—almost one in ten—have either recently used a weight loss drug or are interested in doing so soon. Lead author Professor Sarah Jackson noted that this level of use and interest far exceeds NHS England’s original target of prescribing these medications to 220,000 people over three years. However, the study could not assess whether use reflected genuine medical need, as respondents’ body mass index and health conditions were not recorded.
The research also highlighted safety and equity concerns. Among those using medication for weight loss, around 15% reported taking drugs not licensed in the UK for that purpose, such as Rybelsus, which is approved only for type 2 diabetes. Using medicines “off-label”, particularly without clinical supervision, may increase health risks. The authors stressed that NHS prescribing data captures only a small proportion of overall use, as many people appear to be accessing these drugs privately.
Interest in future use was reported by 6.5% of respondents who had not taken weight loss medication in the past year, with higher interest among women, people aged 45 to 55, and those experiencing psychological distress. Commenting on the findings, Cancer Research UK said that while these drugs can support weight loss, they are not a cure-all and many people regain weight after stopping treatment. The charity emphasised the need for further research, careful medical oversight, and broader action to create healthier environments that support long-term weight management.
More information: Sarah Jackson et al, Prevalence of use and interest in using glucagon-like peptide-1 receptor agonists for weight loss: a population study in Great Britain, BMC Medicine. DOI: 10.1186/s12916-025-04528-7
Journal information: BMC Medicine Provided by University College London
