The objective of this study was to compare the amount of self-reported physical activity, alcohol and tobacco use in a large sample of adults with type 1 diabetes and non-diabetic subjects. A second aim is to test the hypothesis that these lifestyle risk factors are associated cross-sectionally with coronary artery calcification. In 2000-2002, the Coronary Artery Calcification in Type 1 Diabetes (CACTI) study applied validated questionnaires for smoking, alcohol and physical activity to 582 type 1 diabetes subjects and 724 non-diabetic subjects. More type 1 diabetes subjects reported current smoking than non-diabetic subjects (12.3% versus 8.6%, p=0.027). Overall, reported physical activity did not differ by diabetes status (p=0.79). More type 1 diabetes subjects reported never having consumed alcohol (10% versus 4%, p<0.0001) and those who drank consumed less alcohol (p=0.0015) than non-diabetic subjects. Physical activity and smoking were significantly associated with the presence of coronary artery calcification (adjusted OR=0.9, 95% CI: 0.8-0.996, p=0.045, and OR=1.7, CI: 1.1-2.6, p=0.03, respectively). Type 1 diabetes was independently associated with increased odds of coronary artery calcification (OR=3.5, 95% CI: 2.5-5.0, p<0.0001). Differences exist in lifestyle-related cardiovascular risk factors in men and women with type 1 diabetes compared with non-diabetic subjects in the CACTI study.