Pre-diabetes

Pre-diabetes: impaired glucose tolerance and impaired fasting glucose

Prediabetes is a condition that raises the risk of developing type 2 diabetes, heart disease, and stroke. People with prediabetes have blood glucose levels higher than normal but not high enough to be classified as diabetes. People with pre-diabetes have impaired fasting glucose (IFG) or impaired glucose tolerance (IGT). Some people have both IFG and IGT. IFG is a condition in which the fasting blood glucose level is 100 to 125 milligrams per deciliter (mg/dL) after an overnight fast. The level is higher than normal but is not high enough to be classified as diabetes. IGT is a condition in which the blood glucose level is 140 to 199 mg/dL after a 2-hour oral glucose tolerance test. This level is higher than normal but not high enough to be classified as diabetes.
In a cross-section sample of U.S. adults aged 40 to 74 years (tested from 1988 to 1994), 33.8 percent had IFG, 15.4 percent had IGT, and 40.1 percent had pre-diabetes (IGT or IFG or both). Applying these percentages to the entire U.S. population in 2000, an estimated 35 million adults aged 40 to 74 years had IFG, 16 million had IGT, and 41 million had pre-diabetes. Progression to diabetes among those with pre-diabetes is not inevitable. Studies have shown that people with pre-diabetes who lose weight and increase their physical activity can prevent or delay diabetes and even return their blood glucose levels to normal.