What Is Diabetes? When you or someone you love has diabetes, you discover that you must think about a part of life that others take for granted. Your never-changing goal becomes reaching a subtle balance between glucose and insulin. The more you learn about diabetes, the better you can be at your balancing act, and the richer your life shared with this chronic disease can be. TYPES OF DIABETES Diabetes refers to a set of several different diseases. The most common types of diabetes are type 1, or immune-mediated diabetes mellitus, and type 2, or insulin-resistant di- abetes mellitus. A third type of diabetes, gestational diabetes mellitus, occurs during some pregnancies. All types of diabetes have similar symptoms, because all forms of the disease result in too much sugar, or glucose, in the blood. This is because your body is unable to remove glucose from your blood and deliver it to the cells in your body. Your cells use glucose as a source of energy in order to stay alive. But the reasons why your body cannot use glucose from the blood are different for type 1 and type 2 diabetes. People with type 1 diabetes do not make enough insulin. Insulin is a small protein made by the pancreas that helps the body use or store glucose from food. People with type 1 diabetes can be treated with injections of insulin. In contrast, people with type 2 diabetes, like women with gestational diabetes, do make insulin, but for some reason, the cells in their bodies are resistant to insulin's action or they don't make enough insulin. In all types of diabetes, if glucose does not get into the cells and tissues that need it, it accumulates in the blood. About half of all cases of type 1 diabetes appear in childhood or in the early teenage years. For this reason, it used to be called juvenile-onset diabetes. If your symptoms first appeared during the early teenage years, your doctor probably suspected diabetes right away. If you were a young child when the disease developed, it might have occurred so fast that you went into a coma, before anyone suspected diabetes. Type 2 diabetes most often develops in adulthood and used to be called adult-onset diabetes. Usually, it does not appear suddenly. Instead, you may have no noticeable symptoms or only mild symptoms for years before diabetes is detected, perhaps during a routine exam or blood test. Gestational diabetes only appears during pregnancy in women with no previous history of type 1 or type 2 diabetes and goes away after pregnancy. Pregnant women are tested for gestational diabetes. All people with diabetes have one thing in common. They have too much sugar, or glucose, in their blood. People with very high or poorly controlled blood glucose levels share many similar symptoms: an unusual thirst a frequent desire to urinate blurred vision a feeling of being tired most of the time for no apparent reason People with type 2 diabetes may also experience leg pain that may indicate nerve damage or poor circulation. Many people with type 1 diabetes and some people with type 2 diabetes also find that they lose weight even though they are hungrier than usual and are eating more. Even if they have lost weight, people with type 2 diabetes still tend to be overweight. Three-fourths of all people with type 2 diabetes are or have been obese that is, they are at least 20 percent over their desirable body weight (see the chart of suggested body weights for adults). Type 2 diabetes tends to develop in people who have extra body fat. Where you carry your excess fat may determine whether you get type 2 diabetes: Extra fat above the hips (central body obesity) is riskier than fat in the hips and thighs for developing type 2 diabetes. And leading an inactive "couch potato" lifestyle can also lead tBantam Books Staff is the author of 'American Diabetes Association Complete Guide to Diabetes', published 2006 under ISBN 9780553589078 and ISBN 0553589075.