Metabolic syndrome is a complex group of conditions, and the cause is not completely understood. The best scientific evidence suggests that insulin resistance lies at the root. Insulin resistance is associated with obesity, especially abdominal obesity, and can lead to alterations in blood sugar, blood pressure, and blood lipid levels.Metabolic syndrome is a complex group of conditions, and the cause is not completely understood. The best scientific evidence suggests that insulin resistance lies at the root. Insulin resistance is associated with obesity, especially abdominal obesity, and can lead to alterations in blood sugar, blood pressure, and blood lipid levels.