Prediabetes

Diagnosis

The American Diabetes Association (ADA) suggests diabetes screening for most adults starting at age 35. The ADA suggests diabetes screening before age 35 for those who have excess weight and other risk factors for prediabetes or type 2 diabetes. The same tests used to diagnose diabetes also diagnose prediabetes.

If you've had gestational diabetes, your healthcare professional is likely to check your blood sugar levels at least once every three years.

Blood tests for diabetes and prediabetes include:

Glycated hemoglobin (A1C) test

This test shows your average blood sugar level for the past 2 to 3 months.

In general:

• Below 5.7% is healthy.
• Between 5.7% and 6.4% is prediabetes.
• 6.5% or higher on the test done twice means diabetes.

Certain conditions can keep the A1C test from giving a true result. These include pregnancy and a form of hemoglobin that isn't common. Hemoglobin is a protein in red blood cells that carries oxygen from the lungs to the rest of the body.

Fasting blood sugar test

This uses a blood sample you give after not eating for at least eight hours.

Blood sugar values are given in milligrams of sugar per deciliter (mg/dL) or millimoles of sugar per liter (mmol/L) of blood. In general:

• Less than 100 mg/dL (5.6 mmol/L) is healthy.
• 100 to 125 mg/dL (5.6 to 6.9 mmol/L) is prediabetes.
• 126 mg/dL (7.0 mmol/L) or higher on the test done twice is diabetes.

Oral glucose tolerance test

Healthcare professionals use this test less often than the others, except during pregnancy. You fast overnight and then go to a medical office or lab to drink a sugary liquid. A technician tests your blood sugar levels over the next two hours.

In general:

• Less than 140 mg/dL (7.8 mmol/L) is healthy.
• 140 to 199 mg/dL (7.8 to 11.0 mmol/L) suggests prediabetes.
• 200 mg/dL (11.1 mmol/L) or higher after two hours suggests diabetes.

If you have prediabetes, your healthcare professional is likely to check your blood sugar levels at least once a year.

Children and prediabetes testing

Type 2 diabetes is becoming more common in children and adolescents. This is likely due to the rise in childhood obesity.

The ADA suggests prediabetes testing for children who are overweight or children with obesity and who have one or more other risk factors for type 2 diabetes, such as:

• Family history of type 2 diabetes.
• Being of a race or ethnicity linked with an increased risk.
• Low birth weight.
• Being born to a person who had gestational diabetes.

The ranges of blood sugar levels considered healthy, prediabetes and diabetes are the same for children and adults.

Healthcare professionals suggest testing children who have prediabetes for type 2 diabetes yearly. Children who have a change in weight or get symptoms of diabetes may have testing more often. Symptoms include greater thirst, urinating more, tiredness or blurred vision.

Treatment

Healthy lifestyle choices can help you bring your blood sugar level down or at least keep it from rising to type 2 diabetes levels.

To prevent prediabetes from getting to type 2 diabetes:

• Eat healthy foods. A diet rich in fruits, vegetables, nuts and whole grains is linked with a lower risk of prediabetes. Choose foods low in fat and calories and high in fiber. Eat a variety of foods.
• Be more active. Physical activity helps you manage your weight, uses up sugar for energy and helps the body use insulin better. Aim for at least 150 minutes of moderate or 75 minutes of vigorous aerobic activity a week. Or do both moderate and vigorous exercise.
• Get to and stay at a healthy weight. If you are overweight, losing just 5% to 7% of your body weight can greatly lower the risk of type 2 diabetes. This means losing about 14 pounds (6.4 kilograms) for someone who weighs 200 pounds (91 kilograms). To stay at a healthy weight, make long-term changes to your eating and exercise habits.
• Get good sleep. Getting 7 to 8 hours of restful sleep a night may lower the risk of prediabetes turning into type 2 diabetes.
• Stop smoking. Stopping smoking can improve the way insulin works and improve your blood sugar level.
• Take medicines as needed. If you're at high risk of diabetes, your healthcare professional might suggest metformin (Glumetza). You also might take medicines to manage cholesterol and high blood pressure.

Children and prediabetes treatment

Lifestyle changes for children with prediabetes are the same as for adults with type 2 diabetes, including:

• Losing weight.
• Eating fewer fats, fewer refined carbohydrates, such as white bread, and more fiber.
• Cutting the amount of food you eat.
• Eating out less often.
• Spending at least one hour every day doing physical activity.

Healthcare professionals don't often prescribe medicine for children with prediabetes unless lifestyle changes don't lower blood sugar levels. Children who need medicine most often take metformin (Glumetza).

Clinical trials

Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.

Alternative medicine

Some people believe that alternative therapies may treat or prevent type 2 diabetes. But there's no proof that alternative treatments work. Therapies that may help in type 2 diabetes that also are likely to be safe, include:

• Aloe.
• Blond psyllium.
• Caffeine.
• Flaxseed.
• Ginseng.
• Magnesium.
• Oats.
• Soy.
• Xanthan gum.

Talk with your healthcare professional if you want to try dietary supplements or other alternative therapies to treat or prevent prediabetes. Some supplements or alternative therapies may be harmful if taken with some prescription medicines. Your healthcare professional can help you compare the pros and cons of alternative therapies you want to try.

Preparing for your appointment

Start by seeing your main healthcare professional, who may send you to a specialist in diabetes treatment, called an endocrinologist, and a dietitian or a diabetes educator.

Here's information to help you get ready for your appointment.

What you can do

When you call to make the appointment, ask what you need to do before you go. You may need to fast for at least eight hours before your appointment so that your healthcare professional can measure your fasting blood sugar level.

Make a list of:

• Your symptoms, and when they began.
• All medicines, vitamins and supplements you take, including dosages.
• Key personal and medical information, including other conditions, recent life changes and stressors.
• Questions to ask your healthcare professional.

Some basic questions to ask include:

• How can I keep prediabetes from turning into type 2 diabetes?
• Do I need to take medicine? If so, what side effects can I expect?
• I have other health conditions. How can I best manage them together?
• Should I not eat some foods? Can I still eat sugar?
• Do I need to see a dietitian?
• Are there local programs for preventing diabetes?

What to expect from your doctor

Your healthcare professional is likely to ask you questions, such as:

• Has your weight changed recently?
• Do you exercise regularly? If so, for how long and how often?
• Do you have a family history of diabetes?