At what age should you start taking an aspirin per day?

Depends on CAD risk. The age to begin taking Aspirin for cv prevention depends on the patient's risk. For those patients who already have had a heart attack or stroke, Aspirin should be prescribed regardless of age. For those at increased risk, with history of diabetes or peripheral vascular disease, Aspirin should be prescribed. For those without risk factors, generally begin at age 50 for men and 60 for women.