Marks and Spencer, John Lewis and Debenhams have scaled back the proportion of plus-size dresses in their ranges, according to new analysis by retail intelligence platform Edited, amid a surge in the use of weight loss injections such as Mounjaro. The findings, reported by The Daily Telegraph, suggest fashion retailers are recalibrating their offerings as GLP-1 drugs, once used mainly for type 2 diabetes, become increasingly mainstream, with some experts warning this risks "shutting out" larger customers from the high street.

Edited compared new dress listings from July and August this year with the same period in 2024 and found notable falls in the largest sizes. At M&S, dresses sized 18 and above fell from 34% to 27% of new listings, while sizes 22 to 24 dropped from 2.2% to just 0.4%. John Lewis's largest sizes fell from 22.3% to 19.2% of its range, and Debenhams' plus-size dresses fell from 23% to 17.4%, though Debenhams attributed this to its expansion to include more than 25,000 third-party brands rather than a cut to its own offering. By contrast, George at Asda held steady at 43-44%. Mintel research found 8% of British adults have used a GLP-1 injection or similar weight-loss medication, with predictions that up to one in eight Britons could be on such treatment by next year; both M&S and John Lewis said they remained committed to offering extended and inclusive sizing.