Prediabetes is when your blood glucose levels are high but not yet at the level of diabetes. The condition is a risk factor for type 2 diabetes, but is not a disease in itself and is often reversible.

What Is Prediabetes?

With prediabetes, your blood sugar levels are above the healthy range but below the level for a diagnosis of type 2 diabetes.

For most people, healthy blood sugar levels are between 70 and 99 milligrams per deciliter (mg/dL) when fasting. If your fasting glucose levels are between 110 and 125 mg/dL, your doctor may diagnose prediabetes.

People may receive a prediabetes diagnosis with a hemoglobin A1C test result of 5.7–6.4 percent; 6.5 percent or greater indicates diabetes.

The United States Preventive Services Task Force (USPSTF) recommends screening for prediabetes and type 2 diabetes in adults ages 35–70 years who have overweight or obesity. Clinicians should offer or refer patients with prediabetes to effective preventive interventions.

A prediabetes diagnosis can help you manage your long-term health. It acts as a warning that diabetes may develop if you don’t take action to manage your blood sugar levels.

About 70 percent of people with prediabetes will develop type 2 diabetes at some time. But diet, exercise, and weight management can delay or prevent this. Sometimes a doctor will prescribe medication to support these approaches.

Signs and Symptoms of Prediabetes

Over one-third of American adults have prediabetes, but around 90 percent don’t know they have it, because it doesn’t tend to produce symptoms. If symptoms do occur, you might:

• Feel hungrier or thirstier than usual

• Urinate more often

• Notice unexpected weight gain or weight loss

• Feel weak and tired

• Sweat more than usual

• Have blurred vision

• Notice that cuts and bruises take longer to heal

• Have frequent skin infections

• Have bleeding gums

• Have numbness and tingling in your hands and feet

Causes and Risk Factors of Prediabetes

Your chance of developing prediabetes is higher if:

• Your body mass index (BMI) is over 25.

• You have high blood pressure (hypertension).

• Any of your parents or siblings have type 2 diabetes.

• You have polycystic ovarian syndrome (PCOS).

• You have low levels of physical activity.

• You have sleep apnea.

• Your HDL cholesterol levels are below 40 mg/dL for men or 50 mg/dL for women; or your triglyceride levels are over 250 mg/dL.

• You have a history of gestational diabetes, or diabetes during pregnancy.

• You smoke tobacco.

• You are Black American, Hispanic American, Native American, or an Asian or Pacific Islander.

How Is Prediabetes Diagnosed?

If you have overweight or obesity, experts recommend regular screening for prediabetes every three years starting between ages 30 and 45.

A doctor may recommend testing sooner or more often if you have symptoms or risk factors for type 2 diabetes.

Guidelines from the United States Preventive Services Task Force (USPSTF) advise testing for anyone who:

• Is 35 to 70 years old

• Has a BMI over 25

• Has no symptoms

• Is not pregnant

During pregnancy, doctors routinely carry out blood glucose tests at 24 to 28 weeks to check for gestational diabetes. Here are some blood tests doctors use to diagnose prediabetes.

Try the online prediabetes risk test provided on the Centers for Disease Control and Prevention (CDC) website. If the test shows you have a high risk of prediabetes, consider asking your doctor for tests.

Prevention of Prediabetes

Ways to reduce the risk of prediabetes include:

• Maintain a normal body weight.

• Follow a varied and nutritious diet.

• Exercise regularly.

• Avoid smoking.

• Get regular screenings if you have risk factors.

• Manage blood pressure and cholesterol levels.

Lifestyle Changes for Prediabetes

Prediabetes treatment aims to stabilize or reduce blood glucose levels to prevent or delay the progression from prediabetes to type 2 diabetes.

Lifestyle strategies are key to prediabetes treatment.

Make Changes to Your Diet and Nutrition Intake

Dietary tips for a prediabetes diet involve focusing on certain types of food while limiting or avoiding others.

Foods to include in the diet:

• Nonstarchy vegetables

• Quality carbohydrates, such as fruits and whole grains

• Healthy fats, such as olive oil

• Nuts and seeds

• Lean meats

• Plant-based proteins, such as lentils and pulses

• Low-fat dairy products

• Water

• Beverages without added sugar

Foods to limit or avoid:

• Highly processed foods, such as chips and many fast foods

• Foods with a high sugar, salt, or fat content

• Alcoholic drinks

• Saturated fats, present in meats and many commercially produced baked goods

• Sugary sodas and juices

Get Regular Exercise

Regular physical activity can help manage weight, keep your body strong, and boost your mental and physical well-being. There are many things you can do to help you get started with exercise.  For adults, guidelines from the Centers for Disease Control and Prevention (CDC) recommend:

• At least 150 minutes per week of moderate-intensity exercise, for instance, 30 minutes of brisk walking five days a week

• Alternatively, 75 minutes per week of vigorous-intensity exercise, such as jogging, or a combination of moderate and vigorous exercise

• In addition, muscle-strengthening activities two days a week

Manage Weight

A high BMI increases the risk of both prediabetes and diabetes. Weight loss or weight management can help prevent both.

According to the American Diabetes Association, people with obesity or overweight can reduce their risk of type 2 diabetes by 58 percent if they lose 7 percent of their body weight.

For a person weighing 200 pounds, that means losing 15 pounds. Exercise and dietary measures can help you manage your weight.

Treatment and Medication Options for Prediabetes

If diet and exercise don’t help, your doctor may prescribe medication to manage your blood sugar levels and prevent or delay type 2 diabetes.

Options include:

• metformin (Glucophage)

• acarbose (Precose)

• GLP1 receptor agonists (Ozempic)

These drugs don’t have approval from the U.S. Food and Drug Administration (FDA) to treat prediabetes, but doctors can prescribe them off-label.

But several of the anti-obesity medications have been shown to lower the risk of diabetes in people with prediabetes and are indicated in people with a body mass index greater than or equal to 27 kg/m2.

Prediabetes Prognosis

Statistics suggest that around 70 percent of people with prediabetes go on to develop type 2 diabetes at some time, particularly if they are overweight.

But weight management, exercise, dietary choices, and medication can prevent this. In fact, depending on the measurements used, some studies have concluded that, with intervention, 30 to 60 percent of people with prediabetes regain normal glucose levels within one to five years. On the other hand, some research suggests that prediabetes may increase your risk of dying of type 2 diabetes–related complications, such as cardiovascular disease, even if type 2 diabetes has not yet developed.

The outlook for prediabetes can depend significantly on how you implement lifestyle changes.

Complications of Prediabetes

The main complication of prediabetes is the risk of type 2 diabetes. But even a small rise in blood sugar levels can increase the risk of conditions commonly linked to type 2 diabetes. As a result, people with prediabetes also have a higher risk of:

• Cardiovascular disease

• Kidney disease

• Coronary heart disease

• Stroke

• Vision loss

• Peripheral neuropathy

Research and Statistics: Who Has Prediabetes?

Here are some facts and statistics about prediabetes.

• Around 98 million American adults have prediabetes — that’s more than 1 in 3.

• If you have prediabetes, dietary changes and exercise can cut your risk for type 2 diabetes by more than half.

• Prediabetes progresses to type 2 diabetes at a rate of around 5 to 10 percent per year.

• Some 70 percent of people with prediabetes will develop type 2 diabetes at some time in their life.

• Depending on years measured and other factors, an estimated 25 to 85 percent of people will return to normal blood glucose levels.

• In a study with 3,110 participants, 13.9 percent of children (ages 4 to 9 years) and 24.6 percent of adolescents (10 to 17 years) have prediabetes, and up to 20.5 and 31.6 percent of those with severe obesity do.

Disparities and Inequities in Prediabetes

Prediabetes is more common among Black, Native, and Hispanic Americans and Pacific Islanders than among white Americans.

The authors of a study published in 2023 thought the following factors explained these disparities:

• A higher risk of psychological trauma and stress

• A lower household income

• Limited access to healthy food

• Lack of safe spaces for exercise

• Lack of education about prediabetes

• Reduced access to healthcare

• Other environmental exposures

The authors called for better education programs about the risks of prediabetes and the need to address issues such as the availability of healthy foods and exercise spaces.

Related Conditions

Various conditions are related to high blood sugar, whether prediabetes or type 2 diabetes.

They include high blood pressure, cardiovascular disease, and other complications linked to type 2 diabetes and metabolic syndrome.

Prediabetes can also resemble type 1 or 2 diabetes and insulin resistance.