Household consumer purchases and chronic disease

Chronic disease risk stratification remains costly and often provides limited insight into modifiable exposures. Consumer purchases are routinely generated, low-burden measures of household lifestyle that can be linked to health outcomes with consent. In this Danish cohort study, we linked 9.7 million grocery, beverage, and tobacco purchases from 8,382 households, comprising 14,881 adult household members, to six national registries from 2019 to 2023. We examined whether household purchase patterns were associated with prevalent and incident chronic disease and whether they could support risk stratification. Purchases of several additives, sweetened products, and NOVA 4 foods were associated with higher chronic disease risk, whereas purchases of Keyhole-labelled and minimally processed products showed inverse associations. A random forest model combining demographic and purchase variables identified a high-risk decile in which 9% of households developed chronic disease during follow-up. These findings support consumer purchase data as a scalable supplement to existing approaches for studying and monitoring modifiable chronic-disease risk.