[slymon99]

> some third factor like "propensity to consume highly-processed food products" is responsible

Even with the significant controls in the study, I still completely believe this is the case. People who avoid artificial sweeteners likely make many other health-promoting decisions (healthy user bias) that are far too granular to control against using simple factors like weight and smoking status. The HR is only 1.15. Are you really confident enough in the controls to see this as a real association?