What does a prediabetes diagnosis actually mean?

A diagnosis of prediabetes means that you have blood sugar (glucose) levels that are above the normal range but are not considered high enough to be diabetes. However, prediabetes is taking a step in the wrong direction in regards to metabolic health. People with prediabetes have an increased risk of developing type 2 diabetes. The good news is, prediabetes can be reversed before developing any health complications associated with diabetes.

How is prediabetes diagnosed?
Prediabetes is diagnosed by measuring blood glucose levels. The most common test is an HbA1c test, which is available here. This test provides an average blood glucose level for the preceding 2–3 months. An HbA1c test result of 5.7–6.4% is classified as prediabetes (1). For more information about HbA1c testing, see our previous article here.

Prediabetes can also be diagnosed by a glucose test (available here). However, this test often requires fasting (an HbA1c test doesn’t) and only provides a blood glucose level for the specific time that the blood sample was collected. Blood glucose levels fluctuate throughout the day and are dependent on recent food consumption and exercise etc., so a blood glucose test does not provide the same average blood glucose level as the HbA1c test (2). A fasting blood glucose test result of 100–125 mg/dL is indicative of prediabetes (3).

Does prediabetes cause any symptoms?
There are no clear symptoms of prediabetes, which is why many people are unaware of their diagnosis. In fact, more than 84% of approximately 88 million prediabetic American adults do not know that they have prediabetes (4).

What increases the risk of prediabetes?
Several factors increase the risk of prediabetes and type 2 diabetes (2), including:

  • Obesity
  • Family history of type 2 diabetes
  • High blood pressure
  • Altered lipid levels (e.g., elevated LDL “bad” cholesterol)
  • Lack of physical activity
  • Smoking
  • Previously had gestational diabetes

How can I reduce my blood sugar back to normal healthy levels?
If you are overweight, losing even just a small amount of weight (5–7% of your body weight) is beneficial. Combing this weight loss with regular physical activity (150 minutes a week) is the best approach to lower blood glucose levels and reduce the risk of developing type 2 diabetes (4). Read our previous article here for more tips for lowering high blood glucose.

Should I get regular blood sugar tests?
The CDC recommends people over the age of 45 should get screened for diabetes and prediabetes. An HbA1c test is the most informative and convenient test for this screening. People who have normal HbA1c values (<5.7%) usually don’t need to be screened again for three years, while those with prediabetes levels (5.7-6.4%) should be tested again in 1-2 years (1).

People under 45 years with certain risk factors may also need to take an HbA1c test. These risk factors include begin overweight or obese, high blood pressure, history of heart disease, and physical inactivity (1).

References:
1. All About Your A1C. CDC. (Reviewed August 2021)
2. Fonseca V, Inzucchi SE, Ferrannini E. (2009). Redefining the diagnosis of diabetes using glycated hemoglobin. Diabetes Care. 32(7), 1344- 1345.
3. Diabetes Tests. CDC. Reviewed August 2021.
4. Prediabetes – Your chance to prevent type 2 diabetes. CDC. Reviewed June 2020.