According to the Centers for Disease Control and Prevention, some 29 million children and adults in the U.S., or over 9% of the population, have diabetes today. Yet, millions of Americans are unaware that they have diabetes, because there may be no warning signs.
Diabetes and the Fasting Plasma Glucose Test
The fasting plasma glucose test (FPG) is the preferred method for diagnosing diabetes, because it is easy to do, convenient, and less expensive than other tests, according to the American Diabetes Association.
How Do I Prepare for the Blood Glucose Test?
Before taking the blood glucose test, you will not be allowed to eat anything for at least eight hours.
What Happens During the Blood Glucose Test?
What Do the Results of the Blood Glucose Test Mean?
Normal fasting blood glucose -- or blood sugar -- is between 70 and 100 milligrams per deciliter or mg/dL for people who do not have diabetes. The standard diagnosis of diabetes is made when two separate blood tests show that your fasting blood glucose level is greater than or equal to 126 mg/dL.
However, if you have normal fasting blood sugar, but you have risk factors for diabetes or symptoms of diabetes, your doctor may decide to do a glucose tolerance test (see below) to be sure that you do not have diabetes.
Some people have a normal fasting blood sugar reading, but their blood sugar rapidly rises as they eat. These people may have impaired glucose tolerance. If their blood sugar levels are high enough, they may be diagnosed with diabetes.
The Casual Plasma Glucose Test for Diabetes
The casual plasma glucose test is another method of diagnosing diabetes. During the test, blood sugar is tested without regard to the time since the person's last meal. You are not required to abstain from eating prior to the test.
A glucose level greater than 200 mg/dL may indicate diabetes, especially if the test is repeated at a later time and shows similar results.
The Oral Glucose Tolerance Test for Diabetes
The oral glucose tolerance test is yet another method used to detect diabetes, but it is usually only done during pregnancy to diagnose gestational diabetes or for someone who is suspected of having type 2 diabetes yet has a normal fasting glucose level. It can also be performed to diagnose prediabetes.
Diabetes and the Hemoglobin A1c Test
The hemoglobin A1c test (also called the glycated hemoglobin test or HbA1c), is an important diabetes blood test used to determine how well your diabetes is being controlled. This diabetes test provides an average of your blood sugar control over a six- to 12-week period and is used in conjunction with home blood sugar monitoring to make adjustments in your diabetes medicines. The HbA1c level can also be used to diagnose diabetes if a value of equal to or greater than 6.5% is found.
Other Diabetes Tests
Along with the hemoglobin A1c test, it's important for people with diabetes to have a dilated eye exam at least once a year as part of a complete eye exam. This important test can detect early signs of retinopathy, which may have no symptoms at first. A foot exam once or twice a year -- or at every doctor's visit -- is also imperative to detect decreased circulation and sores that may not be healing. Early detection of eye and foot problems in diabetes allows your doctor to prescribe proper treatment when it is most effective.
Diabetes Testing in Children
Talk to your doctor about your child's risk for diabetes. If your child's blood sugar tests are higher than normal, but not yet at the level of diabetes (called prediabetes), your doctor may instruct you in specific diet and exercise changes to help your child avoid getting diabetes altogether. Children with type 2 diabetes or prediabetes are almost always overweight or obese.
Understanding Your Diabetes Diagnosis
Diabetes can cause major health problems if you do not keep your blood sugar in check. However, you can stay healthy and feel good despite your diagnosis if you follow your doctor's recommended treatment plan and maintain a healthy lifestyle. By choosing foods wisely, exercising regularly, maintaining a normal weight, reducing your stress level, and making other modest lifestyle changes, living with diabetes will be easier.