Oral Glucose Tolerance Test

Being called "sweet" is usually seen as a good thing, but when it refers to your blood sugar, trouble could be lurking on the horizon. So, if there is concern your "sweetness" is due to the latter, your health care provider will order a test called the glucose tolerance test.

This gold standard assesses how your body responds to sugar. The glucose tolerance test can be easily performed at your doctors office, only takes a few hours to complete, and is nearly painless. It is an ideal initial assessment because it can be diagnostic for active diabetes or a precursory state known as prediabetes.

Note: this test is only helpful to diagnose high level of sugar in the blood. The other evil cousin, hypoglycemia, or low blood sugar cannot be diagnosed using this method.

Glucose Tolerance Test Preparations

In preparation for the test, you can continue to eat normally, just don’t eat at a Vegas buffet or eat three pounds of pasta the evening before the test. Sometimes your doctor may recommend a more personalized plan, especially if you have any known illnesses or are taking certain medications.

At the beginning of the glucose tolerance test, you’ll be given a cup of sweet syrupy liquid that must be consumed within 5-minutes, then a blood glucose reading will be taken. After waiting an hour, you will receive another fingerstick blood test. Then a second hour must pass before a third assessment is done. Some physicians do another evaluation and continue for a third hour, but the second one will typically be sufficient. If you had a "sweet tooth" coming into this test, it will definitely be cured after drinking all this sugar!

Interpreting the Results of a Glucose Tolerance Test

A number above 200mg/dl for two consecutive readings is a clear indication of diabetes. Yikes! But a blood glucose between 140 and 200 is an indication of being prediabetic. If you receive a prediabetic diagnosis, it’s not the end of the world, but it’s a wake-up call to begin making lifestyle changes to prevent developing full blown diabetes. Analyzing for gestational diabetes is somewhat different as a level of 140mg/dl is confirmatory and if indicated, an evaluation might just take one hour instead of two.

If your blood sugar is mildly high, you will be given ideas for beginning a fitness plan and restricting sugary and processed carbs. But don’t worry, as intelligent changes can amount to big differences in blood sugar levels. If the test results indicate you actually have diabetes, your doctor will likely initially prescribe an oral medication such as metformin to immediately bring down your blood sugar. This is a common prescriptive first step for the treatment of type 2 diabetes. But, if your blood sugar is significantly elevated, or doesn’t respond to oral agents, your doctor may opt for starting you on insulin. If you are prescribed insulin, don’t freak out, because diabetes can be well managed or even reversed in certain situations.

Just remember that a one-time elevated fingerstick blood sugar reading is not necessarily diagnostic for diabetes, but must be confirmed or ruled out by 2 glucose tolerance tests. So for best results, take these results very seriously and work closely with your health care provider to maximize chances of a healthy outcome.

Disclaimer: The information contained herein is for educational purposes only and should not be considered medical advice. Please consult your health care provider before starting any treatment regimen.