Insulin Resistance and the Metabolic Syndrome

Insulin resistance is defined as an impaired biological response to the actions of insulin.1 It was classically described as resistance to insulin mediated glucose uptake in peripheral cells. However, as the metabolic and mitogenic processes of insulin action are better understood, abnormal insulin action in these pathways is being elucidated. Thus, impaired biological response to insulin may be associated with either endogenous or exogenous insulin and can be quantified by changes in several metabolic processes, including carbohydrate, lipid, or protein metabolism or by changes in mitogenic processes.2