  Ubiquitous internet access is reshaping the way we live, but it is
accompanied by unprecedented challenges to prevent chronic diseases planted in
long exposure to unhealthy lifestyles. This paper proposes leveraging online
shopping behaviors as a proxy for personal lifestyle choices to freshen chronic
disease prevention literacy targeted for times when e-commerce user experience
has been assimilated into most people's daily life. Here, retrospective
longitudinal query logs and purchase records from millions of online shoppers
were accessed, constructing a broad spectrum of lifestyle features covering
assorted product categories and buyer personas. Using the lifestyle-related
information preceding their first purchases of prescription drugs, we could
determine associations between online shoppers' past lifestyle choices and if
they suffered from a particular chronic disease. Novel lifestyle risk factors
were discovered in two exemplars -- depression and diabetes, most of which
showed cognitive congruence with existing healthcare knowledge. Further, such
empirical findings could be adopted to locate online shoppers at high risk of
chronic diseases with fair accuracy (e.g., [area under the receiver operating
characteristic curve] AUC=0.68 for depression and AUC=0.70 for diabetes),
closely matching the performance of screening surveys benchmarked against
medical diagnosis. Unobtrusive chronic disease surveillance via e-commerce
sites may soon meet consenting individuals in the digital space they already
inhabit.
