Metabolic syndrome (MetS) is a clinical condition that includes multiple cardiovascular disease risk factors, including obesity, high blood pressure or hypertension, dyslipidemia, and abnormal glucose metabolism. The core metabolic abnormality in MetS is insulin resistance, or impaired insulin-mediated glucose regulation that results in elevated plasma insulin concentration. MetS greatly increases the risk for diabetes, atherosclerosis, and adverse metabolic and cardiovascular outcomes. The syndrome is present in over 25 % of adults in the U.S., with higher rates among racial/ethnic minority groups. Although commonly associated with adult diseases and aging, MetS has also been described in children and adolescents, but at a much lower prevalence of approximately 4-5 %. Because obesity is a key component of the syndrome, the growing childhood epidemic has raised awareness of MetS in children. The rate of MetS among obese children and adolescents is approximately 30 %, with similar racial/ethnic disparity among minority groups as among adults.