Before they are diagnosed with type 2 diabetes, most people have “pre-diabetes”. Pre-diabetes is when a person’s blood glucose level is higher then normal, but not high enough for the diagnosis of diabetes. Pre-diabetes used to be called impaired glucose tolerance or borderline diabetes. The name has been changed for several reasons. Pre-diabetes is a better way of explaining what it means to have higher than normal blood glucose levels. A person with pre-diabetes is likely to develop diabetes and may already be experiencing some health problems. People with pre-diabetes have 1½ times the risk of heart disease compared to people with normal blood glucose.

Either a fasting plasma glucose test or an oral glucose tolerance test (OGTT) can be used to diagnose pre-diabetes. A normal fasting blood glucose is below 100. A person with pre-diabetes has a fasting blood glucose between 100 and 125 mg/dl. If the fasting blood glucose is 126 mg/dl or above, diabetes is diagnosed. In the oral glucose tolerance test a person’s blood glucose is measured after a fast and 2 hours after drinking a high sugar drink. Normal blood glucose is below 140 mg/dl 2 hours after the drink. In pre-diabetes the 2 hour blood glucose level is 140 to 199 mg/dl. If the 2 hour blood glucose is 200 or above, diabetes is diagnosed.

The Diabetes Prevention Program study showed that people with pre-diabetes can prevent or delay the development of type 2 diabetes with a small weight loss and regular exercise. It is recommended that people with pre-diabetes reduce their weight by 5-10% and participate in physical activity for 30 minutes daily. For a person who weighs 200 pounds, a weight loss of 10 to 20 pounds would be beneficial. For some people with pre-diabetes, weight loss and exercise can lower blood glucose to the normal range.

People who are overweight and age 45 or older should be tested for pre-diabetes. People who are overweight and below 45 years, but have another risk factor such as a family history of diabetes, a history of gestational diabetes, or belong to an ethnic group at high risk for diabetes should be tested for pre-diabetes. Ethnic groups at high risk for diabetes are American Indian, Hispanic, African American and Pacific Islander.

Submitted by Karen Halderson, MPH, RD, LD
Extension Diabetes Coordinator
Revised 2/04 Adapted from materials from

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