Types of Diabetes
Diabetes mellitus is a group of diseases characterized by high levels of blood glucose resulting from defects in insulin production, insulin action, or both. Diabetes can lead to serious complications and premature death, but people with diabetes can take steps to control the disease and lower their risk of complications. Nearly 90% of all diagnosed cases of diabetes are Type 2, whereas between 5-10% are Type 1.
Prediabetes is a condition that individuals develop before developing type 2 diabetes, they almost always have "prediabetes"—blood glucose levels that are higher than normal, but not yet high enough to be diagnosed with diabetes. An estimated 79 million people in the United States have prediabetes. Recent research has shown that some long-term damage to the body, especially the heart and circulatory system, may already be occurring during prediabetes.
Type 1 Diabetes
Type 1 was previously call insulin-dependent diabetes mellitus (IDDM) or juvenile-onset diabetes. Type 1 diabetes develops when the body's immune system destroys pancreatic beta cells, the only cells in the body that make the hormone insulin that regulates blood glucose. To survive, people with type 1 diabetes must have insulin delivered by injection or pump. This form of diabetes usually strikes children and young adults, although disease onset can occur at any age. In adults, type 1 diabetes accounts for nearly 5-10% of all diagnosed cases of diabetes. Risk factors for type 1 diabetes may be autoimmune, genetic, or environmental. There is no known way to prevent type 1 diabetes. Several clinical trials for preventing type 1 diabetes are currently in progress or are being planned.
Type 2 Diabetes
Type 2 was previously called non-insulin-dependent diabetes (NIDDM) or adult-onset diabetes. In adults, type 2 diabetes accounts for nearly 90-95% of all diagnosed cases of diabetes. It usually begins as insulin resistance, a disorder in which the cells do not use insulin properly. As the need for insulin rises, the pancreas gradually loses its ability to produce it. Type 2 diabetes is associated with older age, obesity, family history of diabetes, history of gestational diabetes, impaired glucose metabolism, physical inactivity, and race/ethnicity. African Americans, Hispanic/Latino Americans, American Indians, and some Asian Americans and Native Hawaiians or other Pacific Islanders are at particularly high risk for developing type 2 diabetes and its complications. Type 2 diabetes in children and adolescents, although still rare, is being diagnosed more frequently among American Indians, African Americans, Hispanic/Latino Americans, and Asians/Pacific Islanders.
Gestational diabetes is a form of glucose tolerance diagnosed during pregnancy. Gestational diabetes occurs more frequently among African Americans, Hispanic/Latino Americans, and American Indians. It is also more common among obese women and women with a family history of diabetes. During pregnancy, gestational diabetes requires treatment to normalize maternal blood glucose levels to avoid complications in the infant. Immediately after pregnancy, 5-10% of women with gestational diabetes are found to have diabetes, usually type 2 diabetes. Women who have had gestational diabetes have a 40-60% chance of developing diabetes within the next 5-10 years.
Other Types of Diabetes
Other types of diabetes result from specific genetic conditions (such as maturity-onset of diabetes of youth), surgery, infections, pancreatic disease, and other illnesses. Such types of diabetes account for 1-5% of all diagnosed cases.
For more information, visit the public diabetes resource page.