Metabolic syndrome is a clustering of at least three of the five following medical conditions: abdominal obesity, high blood pressure, high blood sugar, high serum triglycerides, and low serum high-density lipoprotein (HDL).Metabolic syndrome is associated with the risk of developing cardiovascular disease and type 2 diabetes. In the U.S., about a quarter of the adult population has metabolic syndrome, and the prevalence increases with age, with racial and ethnic minorities being particularly affected. Insulin resistance, metabolic syndrome, and prediabetes are closely related to one another and have overlapping aspects. The syndrome is thought to be caused by an underlying disorder of energy utilization and storage. The cause of the syndrome is an area of ongoing medical research.