Objective: Fasting insulin concentrations are often used as a surrogate measure of insulin resistance. We investigated the relative contributions of fasting insulin and insulin resistance to cardiometabolic risk and preclinical atherosclerosis. Design and methods: The Relationship between Insulin Sensitivity and Cardiovascular disease (RISC) cohort consists of 1326 European non-diabetic, overall healthy men and women aged 30-60 years. We performed standard oral glucose tolerance tests and hyperinsulinemic euglycemic clamps. As a general measure of cardiovascular risk, we assessed the prevalence of the metabolic syndrome in 1177 participants. Carotid artery intima media thickness (IMT) was measured by ultrasound to assess preclinical atheros...