Prediabetes: How Is It Different From Diabetes? And What Do I Do About It?

All diabetes is not created equal. Most people are at least somewhat familiar with type 1 and type 2, but things get confusing quickly if someone brings up MODY, LADA, gestational diabetes, or type 1.5. But there’s also a type of diabetes for before you even have diabetes: prediabetes.

Prediabetes is like the engagement period between you and a future spouse that you’re really not going to like. Luckily, there’s still time to call off the wedding. Centers for Disease Control estimates that more than 1 in 3 American adults have prediabetes, and the vast majority don’t even know that they have it.

Those with prediabetes are likely to develop type 2 diabetes, and the difference between prediabetes and type 2 is a matter of numbers. As little as one-tenth of a percent in your A1C determines if you have prediabetes or type 2, and so it’s wiser to pay attention to your specific numbers rather than a catch-all label. It may be more helpful to think of prediabetes and type 2 as areas on a spectrum rather than as specific points, and the goal is to move down the spectrum, toward lower and better-controlled blood sugar, rather than up.

Photo: AdobeStock/WayhomeStudio
Photo: AdobeStock/WayhomeStudio

Having prediabetes is not a guarantee that type 2 will develop, but someone is always prediabetic before developing type 2, and having prediabetes puts someone at a higher risk of developing cardiovascular disease. But the upside of being diagnosed with prediabetes is that it can act as a warning (speak now or forever hold your peace!). Receiving the news that you’re prediabetic can provide motivation for making the changes necessary to avoid type 2 and possibly reverse prediabetes.

How is Prediabetes Determined?

Diabetes and prediabetes can be diagnosed using the same tests, and the results will determine your diagnosis. Your blood sugar will be tested using one or more of the following tests:

Photo: AdobeStock/rocketclips
Photo: AdobeStock/rocketclips

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A1C Test

An A1C test (or hemoglobin test) will measure your average blood sugar for the past 2 to 3 months by looking at your hemoglobin. Hemoglobin is a protein in red blood cells that carries oxygen. By measuring the percentage of hemoglobin in your blood that is glycated (covered in glucose), a doctor can tell if your blood sugar is too low, too high, or just where it should be.

An A1C test is done by drawing blood and having it diagnosed in a lab:

  • Normal A1C: less than 5.7%
  • Prediabetes: 5.7%-6.4%
  • Diabetes: 6.5% or higher
Photo: AdobeStock/lightpoet
Photo: AdobeStock/lightpoet

Fasting Plasma Glucose (FPG) Test

As the name implies, this test requires a period of fasting. After not eating or drinking anything but water for 8 to 10 hours, a blood sample is taken and analyzed.

  • Normal FPG: less than 100 mg/dL
  • Prediabetes: 100-125mg/dL
  • Diabetes: 126mg/dL or higher

Oral Glucose Tolerance Test (OGTT)

This test checks your blood sugar levels before you drink a specialized high-sugar drink and then checks again two hours after. It helps your doctor see how your body responds to glucose.

  • Normal Level: less than 140mg/dL
  • Prediabetes: 140-199mg/dL
  • Diabetes: 200mg/dL or higher
Photo: AdobeStock/kaliantye
Photo: AdobeStock/kaliantye

Random Plasma Glucose Test

This is another blood test, but as you may have guessed, it can be done at any time. If you register 200mg/dL or higher, you might have diabetes, especially if you are experiencing other symptoms. If your blood sugar is high, your doctor will likely order more tests.

“NEXT” for symptoms and prevention

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