There is a well-documented and unexplained increase in the incidence of type 1 diabetes in children around the world, and alarmingly, this increase is most rapid in children under age 5. Type 2 diabetes shows a parallel increase, and is also now appearing even in children. About 6.4% of the world’s adults have diabetes – that’s 285 million people. Health expenditures due to diabetes are estimated to be $376-672 billion US dollars in 2010 worldwide, about 12% of total health expenditures, and this figure does not include expenditures on children with diabetes.
Type 2 is the most common type of diabetes, and the type normally associated with obesity and insulin resistance. Type 1, formerly called juvenile diabetes, is an autoimmune disease where the insulin-producing beta cells of the pancreas are destroyed. There are a number of similarities between type 1 and 2 diabetes, and intermediate types exist as well (such as Latent Autoimmune Diabetes in Adults (LADA), also known as “type 1.5”). For example, dysfunctional beta cells are present in both type 1 and type 2 diabetes, and about 10% of people with type 2 test positive for the autoantibodies characteristic of type 1. Excess weight gain and increased insulin resistance have been associated not only with the development of type 2 diabetes but also with type 1. Women who develop gestational diabetes, meanwhile, are at risk to develop either type 1 or type 2 after pregnancy. Many authors propose that type 1 and type 2 can be thought of as two ends of a “diabetes spectrum,” an idea consistent with findings of genetic susceptibility to these diseases.