Diabetes is a condition which affects the production of insulin, a hormone needed by the body to use glucose (a form of sugar) for energy. In type 1 diabetes, the body produces little or no insulin. Patients need regular injections of insulin to stay alive. In type 2 diabetes, the body either doesn't make enough insulin, or is unable to effectively use insulin. Type 2 can sometimes be controlled with diet and exercises. Some patients also need medication.

The American Diabetes Association estimates 20.8 million Americans have diabetes. Every year, 1.5 million more are diagnosed with the condition. Type 1 affects 5 to 10 percent of all patients with the disease and is typically diagnosed during childhood or young adulthood. Type 2 is the most common type of diabetes, affecting 90 to 95 percent of patients. It's typically diagnosed in middle-aged adults who are overweight and sedentary. However, doctors are seeing an increasing number of cases of type 2 among children who are overweight and sedentary.

Diabetes is the sixth leading cause of death in this country. Over time, elevated levels of glucose can damage the blood vessels and organs. Patients with diabetes are 2 to 4 times more likely to die from heart disease or stroke. Diabetics are also at increased risk for blindness, kidney disease, nerve disease, impaired wound healing and amputation.

Pre-diabetes

Pre-diabetes is a condition in which the body has an impaired ability to use glucose. Glucose levels build up in the blood, but don't reach levels needed for a diagnosis of diabetes. It's also known as impaired glucose tolerance and impaired fasting glucose. According to the American Diabetes Association, about 54 million people in the U.S. have pre-diabetes.

The National Institute of Diabetes and Digestive and Kidney Diseases says most people with pre-diabetes develop type 2 diabetes within 10 years. That also puts them at risk for developing heart disease, stroke and other complications of the disease.

Testing for pre-diabetes is the same as that for regular diabetes. A fasting plasma glucose test measures the levels of glucose in the blood after fasting for at least 8 hours. A blood sugar level of 99 mg/dL of blood or lower is considered normal. Pre-diabetes is a fasting blood glucose level in the range of 100 mg/dL to 125 mg/dL. Diabetes is considered when fasting blood sugar levels reach 126 mg/dL or higher on two different testing dates.

The second screening test for pre-diabetes is the oral glucose tolerance test. Levels of blood glucose are first measured after an eight hour fast, then two hours after drinking a beverage with a high concentration of glucose. A normal blood sugar level after the oral glucose tolerance test is 139 mg/dL or lower. Pre-diabetes is a reading of 140 to 199 mg/dL. Diabetes is diagnosed at a level of 200 mg/dL or higher on two different testing dates.

People who develop pre-diabetes may be able to reduce their risk for diabetes. A study by the Diabetes Prevention Program found losing just 5 to 10 percent of body weight and getting 30 minutes of moderate physical activity a day can decrease the risk of developing diabetes by 58 percent. That's important because research suggests people with pre-diabetes may already be experiencing damage to their blood vessels and heart - even though they haven't yet developed diabetes.

For general information about pre-diabetes or diabetes:

American Diabetes Association

National Diabetes Education Program

National Diabetes Information Clearinghouse