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Diabetes Testing

If you experience symptoms of severe increased thirst, frequent urination, unexplained weight loss, increased hunger, tingling of your hands or feet -- your doctor may run a test for diabetes. 

According to the Centers for Disease Control and Prevention, almost 26 million children and adults in the U.S., or over 8% of the population, have diabetes today. Yet, millions of Americans are unaware that they have diabetes, because there may be no warning signs.

Did You Know?

Under the Affordable Care Act, many health insurance plans will cover preventive care services, including screening tests for type 2 diabetes, at no cost to you. Learn more.

Health Insurance Center

To confirm the diagnosis of type 2 diabetes, your doctor will order a fasting plasma glucose test or a casual plasma glucose.

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?

During a blood glucose test, blood will be drawn and sent to a lab for analysis.

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 intolerance. 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.

For more detail, see WebMD's article Oral Glucose Tolerance Test.

WebMD Medical Reference

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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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