If the body does not produce enough insulin to move the sugar into the cells, the resulting high levels of sugar in the blood and the inadequate amount of sugar in the cells together produce the symptoms and complications of diabetes. Doctors often use the full name diabetes mellitus, rather than diabetes alone, to distinguish this disorder from diabetes insipidus, a relatively rare disorder that does not affect blood sugar levels
Types
Prediabetes: Prediabetes is a condition in which blood sugar levels are too high to be considered normal but not high enough to be labeled diabetes. People have prediabetes if their fasting blood sugar level is between 101 mg/dL and 126 mg/dL or if their blood sugar level 2 hours after a glucose tolerance test is between 140 mg/dL and 200 mg/dL. Identifying people with prediabetes is important because the condition carries a higher risk for future diabetes as well as heart disease. Decreasing body weight by 5 to 10 % through diet and exercise can significantly reduce the risk of developing future diabetes.
Type 1: In type 1 diabetes (formerly called insulin-dependent diabetes or juvenile-onset diabetes), more than 90% of the insulin-producing cells of the pancreas are permanently destroyed. The pancreas, therefore, produces little or no insulin. Only about 10% of all people with diabetes have type 1 disease. Most people who have type 1 diabetes develop the disease before age 30.
Type 2: In type 2 diabetes (formerly called non-insulin-dependent diabetes or adult-onset diabetes), the pancreas continues to produce insulin, sometimes even at higher-than-normal levels. However, the body develops resistance to the effects of insulin, so there is not enough insulin to meet the body's needs.
Type 2 diabetes was once rare in children and adolescents but has recently become more common. However, it usually begins in people older than 30 and becomes progressively more common with age. About 15% of people older than 70 have type 2 diabetes. People of certain racial and ethnic backgrounds are at increased risk of developing type 2 diabetes: blacks, Native Americans, and Hispanics who live in the United States have a twofold to threefold increased risk. Type 2 diabetes also tends to run in families.
author: merck