Diabetes Prevention Guide
Your Prediabetes Questions Answered
The more you know — beyond how it's 'not quite' diabetes — the better you can protect yourself
En español | While more than one in three adults have prediabetes, very few know it. That means the red-flag condition can’t send its important message that diabetes may be right around the corner (and that you may already be at risk for some serious cardiovascular issues.) Here’s how to recognize and manage prediabetes in time to turn things around.
What is prediabetes?
Prediabetes indicates your blood sugar levels are higher than they should be, but not yet high enough to be considered diabetes. Not all people with prediabetes go on to develop type 2 diabetes. But almost all people with the type 2, the most common form of diabetes, start out with prediabetes. For some people with the condition, early treatment, as well as moderate lifestyle changes can actually return blood sugar levels to a normal range, effectively preventing or delaying diabetes. Prediabetes itself is often reversible (more on that below.)
What causes prediabetes?
The same factors that raise your risk for type 2 diabetes can set you up for a diagnosis of prediabetes. With the condition, cells in your body aren’t responding normally to insulin, a hormone made by your pancreas that acts like a key to let blood sugar into cells to use as energy. Your pancreas responds by making more insulin, but eventually, as cells continue to not respond, it can’t keep up. At that point, your blood sugar rises, setting the stage for prediabetes — and, by extension, diabetes.
If it isn’t full-blown diabetes, why does it matter?
The “pre” may lead you to believe the condition isn’t serious, but prediabetes puts you at a higher risk for not only diabetes, but also heart disease and stroke. Experts have known about the link between diabetes and cardiovascular disease for a while now, including that cardiovascular disease is the most common cause of death among people with diabetes.
But more recent research shows that people with prediabetes are also at substantial risk of developing cardiovascular disease. That risk is especially pronounced in the first five years of prediabetes. If you do nothing about prediabetes, your risk of developing cardiovascular disease — which includes high blood pressure, heart disease, stroke, and other disorders of the heart and blood vessels — is about 50 percent.
Of the estimated 88 million adults in the U.S. with prediabetes, about two percent per year go on to develop diabetes. That may sound insignificant, but it comes out to about 1.75 million people.
What are the symptoms?
Some people with prediabetes experience increased thirst, frequent urination, fatigue and blurred vision — which are also signs of diabetes. But more often than not, there are no clear symptoms. That’s why it’s important to talk to your doctor about having your blood glucose tested if you have any of the following risk factors:
- You’re 45 or older.
- You’re overweight.
- You have a parent, brother or sister with type 2 diabetes.
- You lead a sedentary life.
- You’ve had diabetes during pregnancy (gestational diabetes) or given birth to a baby that weighed more than 9 pounds.
How can I find out if I have prediabetes?
The only way to know for sure if you have prediabetes is to ask your health care provider to run one of the following three types of blood tests. If you’re diagnosed with prediabetes, you should be checked for type 2 diabetes every one to two years.
This simple blood test measures your average blood sugar for the past two to three months. The advantages of being diagnosed this way are that you don’t have to fast or drink large amounts of anything. Note: Your doctor may report your A1C results as eAG, or “estimated average glucose,” which directly relates to your A1C.
|Normal:||< 5.7 percent||<117 mg/dl|
|Prediabetes:||5.7-6.4 percent||117-138 mg/dl|
|Diabetes:||≥ 6.5 percent||≥139 mg/dl|
Fasting Plasma Glucose (FPG) Test
This test checks your fasting blood sugar levels. Since it requires fasting— taking in nothing but water for at least eight hours before the test — it’s usually done first thing in the morning.
Oral Glucose Tolerance Test (OGTT)
This two- to three-hour test measures your body’s response to sugar. Your doctor will check your blood sugar levels before you drink a special sweet drink and again two hours later.
Is prediabetes reversible?
Yes. In the early stages of prediabetes (and diabetes, for that matter), paying attention to diet and exercise can improve blood sugar numbers, essentially “reversing” the disease and reducing the odds of developing diabetes. But if you have underlying risk factors that put you at greater risk for diabetes — say, for instance, you’re over age 45 or diabetes runs in your family — you’ll need to continue to pay attention to blood sugar levels and lifestyle choices. Otherwise, your prediabetes will return.
What can I do today to help mitigate my risk?
- Talk with your health care provider to run a blood glucose test that will tell you if you have prediabetes or not.
- Get moving — incorporate walking or other exercise into your daily routine. The American Diabetes Association (ADA) recommends 150 minutes of moderate-intensity aerobic activity, as well as two to three strength training sessions, per week. Not only will that sort of commitment to exercise help keep your weight in check, it also improves blood glucose levels.
- Eat healthy and nutritious meals that feed the mind and body. There is no “prediabetes diet” (or, for that matter, a “diabetes diet”). The ADA recommends a number of eating plans, including Mediterranean, low-carb, vegetarian, and others that emphasize non-starchy vegetables, whole, minimally processed foods and little added sugar.
- Maintain a healthy weight. If you’re overweight, even a little weight loss can help. A landmark study at the National Institutes of Health (NIH) found that lifestyle changes leading to a weight loss of 7 percent in overweight participants with prediabetes reduced their risk of diabetes by 58 percent. Participants over age 60 reduced their chances of developing diabetes by 71 percent, compared to those who didn’t lose weight.
- Talk to your doctor about whether it makes sense for you to take the drug metformin. Considered the first-line treatment to help control blood sugar for people with type 2 diabetes, the drug is also recommended by the ADA for people with prediabetes and certain other risk factors. The NIH study found that overweight participants with prediabetes who took metformin lowered their chances of developing diabetes by 31 percent, compared to those who didn’t take the drug or undergo lifestyle changes. The Food and Drug Administration hasn’t approved metformin — or any other medication —for prediabetes, so it is prescribed “off-label.”
- Take the ADA’s prediabetes risk test (available in English and Spanish) to see if you or a family member are at risk.
Where can I get support?
If you have prediabetes, a support group can help you make the necessary lifestyle changes to avoid progressing to diabetes. Not sure how to find one? The ADA organizes workshops geared to a variety of different groups. To find one near you, contact the ADA (800-DIABETES).
The Centers for Disease Control and Prevention (CDC) National Diabetes Prevention Program can also help you learn about healthy lifestyle changes — related to eating habits, exercise and more — shown to reverse prediabetes. The program is offered at YMCAs, community centers, churches and hospitals across the country. To find one near you, enter your zip code into the CDC’s program finder tool. While there are not many CDC programs covered by Medicare yet, you may look for Medicare-covered classes near you by entering your zip code here. You should always ask about coverage to make sure you are not charged any unexpected costs.
Editor's note: This article was originally published on November 2, 2018. It was updated on January 8, 2021.