Weight-loss medications have surged in popularity over the last few years, with more than two million people in the UK now using them. But while drugs like Wegovy and Mounjaro have helped people reduce their weight, they also seem to be reshaping some users' spending habits.

In June, market research company Worldpanel by Numerator published a study looking at how this affects grocery spending among UK users. The research was based on survey responses and observed purchase data from more than 11,000 households in February. A key finding was that households with at least one GLP-1 user spent on average £418 less on groceries in the year after they began their medication, compared with non-users. This amounted to a fall of £780m in grocery spending nationally, it estimated.

People also cut back on buying some items and started spending more on others when taking weight-loss medications. The control group reported spending less on chocolate and pastries and more on fruit and protein-rich foods like prawns. But they bought more chewing gum, mouthwash and hair dyes - products that counter common GLP-1 side effects like thinning hair and bad breath. As Nishita Pattni, a senior consultant at Worldpanel, put it: "This isn't simply a story of shrinking demand. It's also a story of shifting demand."

Weight-loss jabs also appear to be affecting how much people spend on eating out. Nearly two-thirds of those surveyed by Worldpanel reported cutting out or trying to reduce meals out since starting their jabs. Cornell's research, meanwhile, found an 8% decline in spending at fast-food chains and coffee shops. However, the cost of the drugs is a concern: the vast majority of UK patients pay privately, with prescriptions costing more than £300 a month. A survey of 167 users by Zava found the number one reason people stopped taking their medication was cost.