Prediabetes means that your blood sugar level is higher than normal but not yet high enough to be classified as type 2 diabetes. Without intervention, prediabetes is likely to become type 2 diabetes in 10 years or less. If you have prediabetes, the long-term damage of diabetes — especially to your heart and circulatory system — may already be starting.

There's good news, however. Prediabetes can be an opportunity for you to improve your health. Progression from prediabetes to type 2 diabetes isn't inevitable.

With healthy lifestyle changes — such as eating healthy foods, including physical activity in your daily routine and maintaining a healthy weight — you may be able to bring your blood sugar level back to normal.

Symptoms Causes Risk factors Complications Prevention

Often, prediabetes has no signs or symptoms.

One possible sign that you may be at risk of type 2 diabetes is darkened skin on certain parts of the body. This condition is called acanthosis nigricans. Common areas that may be affected include the neck, armpits, elbows, knees and knuckles.

Classic red flags that suggest you've moved from prediabetes to type 2 diabetes include:

  • Increased thirst
  • Frequent urination
  • Fatigue
  • Blurred vision

When to see a doctor

Consult your doctor if you're concerned about diabetes or if you notice any type 2 diabetes signs or symptoms — increased thirst and frequent urination, fatigue, and blurred vision.

Ask your doctor about blood glucose screening if you have any risk factors for prediabetes, such as:

  • You're overweight, with a body mass index above 25
  • You're inactive
  • You're age 45 or older
  • You have a family history of type 2 diabetes
  • You're African-American, Hispanic, American Indian, Asian-American or a Pacific Islander
  • You developed gestational diabetes when you were pregnant or gave birth to a baby who weighed more than 9 pounds (4.1 kilograms)
  • You have polycystic ovary syndrome — a condition characterized by irregular menstrual periods, excess hair growth and obesity
  • You have high blood pressure
  • Your high-density lipoprotein (HDL) cholesterol is below 35 milligrams per deciliter (mg/dL) (0.9 millimoles per liter, or mmol/L) or your triglyceride level is above 250 mg/dL (2.83 mmol/L)

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