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How Is Prediabetes Diagnosed?

To determine if you have prediabetes, your doctor can perform one of three different blood tests -- the fasting plasma glucose (FPG) test, the oral glucose tolerance test (OGTT), or the hemoglobin A1C (or average blood sugar) test.

During the FPG blood test your blood sugar level is measured after an 8 hour fast. This laboratory health screening can determine if your body metabolizes glucose correctly. If your blood sugar level is abnormal after the fasting plasma glucose (FPG) test, you could have what's called "impaired fasting glucose," which suggests prediabetes.

Understanding the FPG Test Results

NormalLess than 100 mg/dL (milligrams per deciliter)
Prediabetes100 mg/dL - 125 mg/dL
Diabetes126 mg/dL or greater on two or more tests

Another laboratory health screening test your doctor can perform is the oral glucose tolerance test (OGTT). During this test, your blood sugar is measured after a fast and then again 2 hours after drinking a beverage containing a large amount of glucose. Two hours after the glucose beverage, if your glucose is higher than normal, you have what's called "impaired glucose tolerance," which suggests prediabetes.

Understanding the OGTT Test Results

ConditionOGTT at 2 hours
NormalLess than 140 mg/dL
Prediabetes140 mg/dL to 199 mg/dL
DiabetesGreater than 200 mg/dL

Hemoglobin A1C Test

The hemoglobin A1C test is a simple blood test that reflects the average blood sugar for the past 2 to 3 months. It can be used to check if your diabetes is under control, but it can also be used to diagnose diabetes.

Normal: 5.6% or less

Prediabetes: 5.7 to 6.4%

Diabetes: 6.5 % or above

Why Is It Important to Recognize and Treat Prediabetes?

By identifying the signs of prediabetes before diabetes occurs, you can prevent type 2 diabetes altogether and lower your risk of complications associated with this condition, such as heart disease.

A research study called the Diabetes Prevention Program (DPP) found that many people who made healthy changes in their diet and who increased their physical activity were able to prevent diabetes. And many were able to return their blood sugar levels back into the normal range. The DPP found that just 30 minutes of moderate physical activity a day coupled with a 4 to 7% weight loss produced almost a 60% reduction in diabetes.

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If the level is below 70 or you are experiencing symptoms such as shaking, sweating or difficulty thinking, you will need to raise the number immediately. A quick solution is to eat a few pieces of hard candy or 1 tablespoon of sugar or honey. Recheck your numbers again in 15 minutes to see if the number has gone up. If not, repeat the steps above or call your doctor.

People who experience hypoglycemia several times in a week should call their health care provider. It's important to monitor your levels each day so you can make sure your numbers are within the range. If you are pregnant always consult with your health care provider.

Congratulations on taking steps to manage your health.

However, it's important to continue to track your numbers so that you can make lifestyle changes if needed. If you are pregnant always consult with your physician.

Your level is high if this reading was taken before eating. Aim for 70-130 before meals and less than 180 two hours after meals.

Even if your number is high, it's not too late for you to take control of your health and lower your blood sugar.

One of the first steps is to monitor your levels each day. If you are pregnant always consult with your physician.

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