There are over 25 million people living in the United States with diabetes, according to the 2011 National Diabetes Fact Sheet from the Centers for Disease Control and Prevention. Of these, 7 million people are undiagnosed. Diabetes is a disease in which blood glucose, or sugar, levels are above normal. It is the leading cause of blindness, kidney failure, and nontraumatic lower extremity amputations. Knowing your blood glucose levels is the first step you can take to prevent or manage diabetes.
Types of Diabetes
There are several types of diabetes, but the two main types are type 1 and type 2. Type 1 diabetes, formerly called juvenile diabetes because it predominantly occurred in children and young adults, accounts for approximately 10 percent of diabetes cases. We now know that type 1 diabetes can occur at anytime throughout the lifecycle. Type 2 diabetes, previously called adult-onset diabetes because it rarely occurred in children and young adults, accounts for approximately 90 percent of diabetes cases. Results from the National Heart, Lung, and Blood Institute's Framingham Heart Study published in 2006 found that the incidence of type 2 diabetes is increasing, secondary to overweight, obesity, and physical inactivity in the United States. Both types of diabetes can be prevented and controlled through diet, physical activity, early detection, blood glucose monitoring and physician-prescribed medication.
Diagnosis of Diabetes
There are two primary clinical tests for diagnosing diabetes. The fasting plasma glucose, or FPG, test measures a person's blood glucose levels after not eating for at least 8 hours. A FPG less than 100 mg/dL is normal, between 100 and 125 mg/dL is impaired and greater than 125 mg/dL may be prognostic of diabetes. The oral glucose tolerance test, or OGTT, is a measurement of how efficiently the body clears blood glucose after a meal. An OGTT less than 140 mg/dL is normal, between 140 to 199 mg/dL is impaired and greater than 200 mg/dL may be prognostic of diabetes. A FPG of 130 mg/dL may indicate diabetes and requires further assessment by a physician. An OGTT of 130 mg/dL is within normal limits. Individuals diagnosed with pre-diabetes or diabetes may benefit from monitoring their pre-meal and post-meal blood glucose levels on a daily basis.
Pre-meal Blood Glucose Levels
For non-diabetics, pre-meal blood glucose levels should be less than 110 mg/dL. For diabetics, pre-meal blood glucose levels should be 90 to 130 mg/dL. A pre-meal blood glucose level of 130 mg/dL is at the upper end of the normal range for diabetics; however, pre-meal blood glucose goals vary among individuals. Consult with your physician to determine the appropriate pre-meal blood glucose goal for yourself.
Post-meal Blood Glucose Levels
For non-diabetics, post-meal blood glucose levels, defined as 1 to 2 hours after a meal, should be less than 140 mg/dL. For diabetics, post-meal blood glucose levels should be less than 180 mg/dL. A post-meal blood glucose level of 130 mg/dL is within normal limits for both diabetics and non-diabetics; however, post-meal blood glucose levels also vary among individuals. Consult with your physician to determine the appropriate post-meal blood glucose goal for yourself.
References
- Centers for Disease Control and Prevention: 2011 National Diabetes Fact Sheet; Feb. 7, 2011
- "Circulation"; Trends in the Incidence of Type 2 Diabetes Mellitus From the 1970s to the 1990s: The Framingham Heart Study; Caroline S. Fox, MD, MPH, et al.; June 2006
- National Diabetes Information Clearinghouse; Diagnosis of Diabetes; Oct. 2008
- American Diabetes Association: American Diabetes Association Self-Assessment Program
