Johns Hopkins Health Alerts Topic Page:
Diabetes
View All Diabetes Health Alerts • View All Diabetes Special Reports
Johns Hopkins Health Alerts | Diabetes
What is diabetes? The term “diabetes mellitus” is derived from the Greek word for siphon (a tube bent in two through which liquid flows) and the Latin word “mellitus,” which means sweet as honey.
Diabetes mellitus, also referred to simply as diabetes, is a metabolic disorder characterized by abnormally high levels of glucose (sugar) in the blood. Diabetes occurs when the body’s production of insulin is inadequate or its response to insulin is insufficient—a condition called insulin resistance. Insulin is a hormone produced by the pancreas that regulates the production of glucose by the liver and the utilization of glucose by cells.
About 24 million individuals in the United States have diabetes. Unfortunately, about six million of them do not even know they have it. They may not have noticed any symptoms yet and have not been checked by their doctor for diabetes. Another 57 million Americans have prediabetes—a condition in which blood glucose levels are higher than normal (100 to 125 mg/dL).
There are several kinds of diabetes, but the two most common are:
- Type 1 diabetes: In this type (formerly called insulin-dependent diabetes), the immune system attacks and destroys beta cells in the pancreas so it can no longer produce sufficient amounts of insulin. Type 1 diabetes is sometimes called juvenile-onset diabetes because it most often starts in childhood. It can develop in adults, but this is far less common.
- Type 2 diabetes: In this type (formerly called adult-onset diabetes), beta cells still produce insulin, but the quantity may be reduced or the body’s cells may be insulin resistant. Most people with type 2 diabetes are obese. This type of diabetes develops gradually and is usually diagnosed in adulthood. However, more and more children are being diagnosed with the disease as the frequency of childhood obesity rises.
How Johns Hopkins can help. If you or someone you care about has diabetes, obtaining accurate information is an important part of the treatment plan. The more you know about diabetes, the better prepared you will be to participate in your own diabetes management.
- At Johns Hopkins Health Alerts, Christopher D. Saudek, M.D., Director of the Johns Hopkins Diabetes Center, Simeon Margolis, M.D., Ph.D., Professor of Medicine at Johns Hopkins, and other leading diabetes experts review the most up-to-date information on the causes, symptoms, and advances in treatments for both types of diabetes—including insulin and oral drugs, lifestyle changes, and ways to reduce the risks of long-term complications from diabetes.
- You’ll find articles on: keys to prevention, insulin choices, diabetic retinopathy, diabetes and your genes, managing diabetes during illness, exercise and diabetes, metabolic syndrome, and much more.
For more information on Diabetes please visit the BOOKSTORE .

