GoodRx Guide
What Is Prediabetes? Symptoms, Causes, and Treatment
Comprehensive information for you or a loved one — including treatment options and discounts on popular medications.
What is prediabetes?
Prediabetes is a condition that describes abnormal blood sugar levels. It’s diagnosed when someone’s blood sugar levels are higher than they should be, but don’t qualify for a diagnosis of Type 2 diabetes. Prediabetes can be thought of as a precursor to diabetes. It’s also known as “impaired glucose tolerance” and “impaired fasting glucose,” but these terms are less common.
People with prediabetes are at high risk for developing Type 2 diabetes. Prediabetes also raises your risk of heart disease and stroke. But, when diagnosed and treated early, people with prediabetes can reverse the condition and slow or even stop the development of Type 2 diabetes.
What causes prediabetes?
Prediabetes is caused by the same problems with insulin that can eventually lead to Type 2 diabetes. The body needs insulin to remove glucose from the blood, so that the body can use it for energy. If there isn’t enough insulin, glucose remains in the blood and can’t be used by the rest of the body.
Diabetes develops for two reasons:
The body doesn’t naturally produce enough insulin.
The body is insulin-resistant, meaning it doesn’t use insulin properly.
Like Type 2 diabetes, prediabetes can occur at any age, but it more often develops later in life.
There’s a genetic link, but other factors also play a very important role in developing prediabetes, including:
Symptoms of prediabetes
In some cases, people with prediabetes can develop acanthosis nigricans, a skin condition that’s common in people with insulin resistance. This often looks like a thick, dark patch of skin on one or more of the following areas:
Back of the neck
Armpit
Groin
Face
Elbows
Knuckles
Many people with prediabetes have no symptoms. And, by the time symptoms appear, it’s likely that you’ve already developed diabetes.
Early signs of diabetes include:
Increased hunger or thirst
Having to pee a lot
Fatigue
Weight loss
Screening for prediabetes
Prediabetes diagnosis relies on screening blood tests.
You should be screened for prediabetes if you:
Are 45 years or older
Have a body mass index (BMI) of 25 or higher
Have high blood pressure
Exercise fewer than 3 times per week
Have a parent or sibling with Type 2 diabetes
Are African American, Hispanic or Latino American, American Indian, Asian American, or Pacific Islander
For women, specifically, there are additional reasons to be screened:
You have polycystic ovary syndrome (PCOS).
You had diabetes during pregnancy.
You gave birth to a baby that weighed more than 9 lbs.
This online test from the CDC will help you get a better idea of your prediabetes risk.
Quiz: Do I have diabetes?
How is prediabetes diagnosed?
There are several blood tests that are used to diagnose prediabetes. These are the same tests used to diagnose Type 2 diabetes. The results — and degree to which they’re abnormal — determine whether you have normal blood sugar, prediabetes, or diabetes.
The blood tests used to diagnose diabetes are:
Fasting blood glucose test: This tests your blood sugar level when you’ve been fasting for 8 hours. A normal result is less than 100 mg/dL. Prediabetes is diagnosed if the result is 100 mg/dL to 125 mg/dL.
Oral glucose tolerance test: This tests your blood sugar 2 hours after you’ve been given a specific amount of sugar. A normal result is less than 140 mg/dL. Prediabetes is diagnosed if the value is 140 mg/dL to 199 mg/dL.
Hemoglobin A1C test: This test gives a picture of your average blood sugar over the past 2 to 3 months. It can be taken at any time, and doesn’t require fasting or having a recent meal. A normal result is less than 5.7%. Prediabetes is diagnosed if the result is 5.7% to 6.4%.
Prediabetes treatment
Treatment for prediabetes is all about lifestyle changes. People with prediabetes are encouraged to make changes to their diet and exercise routine, which can completely reverse the condition and prevent progression to Type 2 diabetes. About one-third of people who make these changes successfully reverse their condition.
These lifestyle changes include:
A balanced diet: There’s no specific diet plan recommended to people with prediabetes. Any diet that reduces the number of calories, carbohydrates, and fat is effective.
Physical activity: This is also flexible, and can be as simple as going for a walk every day. The ADA recommends aiming for 150 minutes of exercise per week.
Weight loss: Research has shown that you may need to lose 7% of your body weight to have a meaningful impact on your blood glucose levels.
Treatment always starts with a steady diet and exercise routine. But, if your blood glucose levels remain elevated after these changes, a healthcare professional may consider prescribing a medication called metformin. Metformin is a common oral medication prescribed to people with diabetes, and research has shown it can also help reverse prediabetes.
Frequently asked questions
Yes, most of the time prediabetes exists before Type 2 diabetes. There are some rare exceptions, like when people develop diabetes from other medical conditions or medication. But most people who develop Type 2 diabetes likely had prediabetes first. This is why screening for prediabetes is so important. It catches the condition early and, if you use the lifestyle strategies detailed above, you can prevent its progression to Type 2 diabetes.
Yes, kids can get prediabetes. More children are developing Type 2 diabetes now, which is linked to an unbalanced diet, not getting enough exercise, and being overweight. Girls are more likely than boys to develop prediabetes and Type 2 diabetes. Screening for prediabetes in children can help detect it early. And early detection means parents can help their children with certain lifestyle strategies (detailed above), which can prevent them from developing Type 2 diabetes.
Metabolic syndrome is a collection of signs that suggest your metabolism is abnormal. It’s a syndrome that identifies people who are at risk for certain conditions, like diabetes. Having an elevated blood sugar level — in the prediabetes range — is part of this syndrome. If you’re diagnosed with prediabetes, you’ll be screened for other signs of metabolic syndrome. This includes measuring your blood pressure, cholesterol levels, and waist size.
A nutritious diet is an important part of treating — and reversing — prediabetes.
Some foods to limit or avoid altogether are:
Beverages with added sugar (soda, juice, flavored coffee drinks)
Foods with added sugars (particularly those with high-fructose corn syrup)
Foods with trans fat (Look for the term “partially hydrogenated” in the oils listed on the ingredient list.)
Some fruits with high amounts of sugar (like dried fruits, bananas, pears, cherries, and grapes)
References
American Academy of Dermatology Association. (n.d.). Acanthosis nigricans: Signs and symptoms.
American Diabetes Association. (n.d.). Understanding diabetes diagnosis.
American Diabetes Association. (n.d.). Weekly exercise targets.
Centers for Disease Control and Prevention. (2022). Prediabetes risk test.
Centers for Disease Control and Prevention. (2024). Diabetes risk factors.
Centers for Disease Control and Prevention. (2024). Prediabetes – Your chance to prevent Type 2 diabetes.
Diabetes Prevention Program Research Group. (2002). Reduction in the incidence of Type 2 diabetes with lifestyle intervention or metformin. New England Journal of Medicine.
Lyssenko, V., et al. (2008). Clinical risk factors, DNA variants, and the development of Type 2 diabetes. New England Journal of Medicine.
National Heart, Lung, and Blood Institute. (n.d.). Calculate your body mass index. National Institutes of Health.
Paprott, R., et al. (2018). Determinants of change in glycemic status in individuals with prediabetes: results from a nationwide cohort study in Germany. Journal of Diabetes Research.
