Diabetes: At a Glance
In diabetes mellitus, blood sugar (glucose) levels are abnormally high because the body does not produce enough insulin to meet the body’s needs. Insulin, a hormone produced by the pancreas, controls the amount of glucose in the bloodstream.
For a full discussion, see Diabetes Mellitus.
There are two types of diabetes mellitus:
Type 1: More than 90% of the insulin-producing cells of the pancreas are destroyed. The pancreas, therefore, produces little or no insulin. Most people who have type 1 diabetes develop the disease before age 30.
Type 2: 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.
Diabetes affects children and adolescents as well as adults. Type 1 can develop at any time during childhood, even during infancy, but it usually begins between ages 6 and 13 years. Type 2 occurs mainly in adolescents but is becoming increasingly common among overweight or obese children.
The main risk factor for type 2 diabetes is
People with diabetes urinate large volumes frequently (polyuria).
The excessive urination leads to abnormal thirst (polydipsia).
Because excessive calories are lost in the urine, people may lose weight. Thus, people often feel excessively hungry.
Other symptoms include blurred vision, drowsiness, nausea, and decreased endurance during exercise.
However, many people have type 2 diabetes for years before they are diagnosed.