Bern Loyalty-Card Study: GLP-1 Users Bought More Produce and Fiber at 5 Months, but Their Groceries Drifted Back by 10 Months
Inselspital Bern researchers matched household loyalty-card data from two major Swiss grocers for 56 adults with obesity and 92 normal-weight controls. After starting a GLP-1 drug, the obesity group's purchases shifted toward protein, fiber, fruit, vegetables, and unprocessed foods at 5 months, but by 10 months they no longer differed meaningfully from before treatment. The authors note the small sample and household-level data limit precision.