Home > Patients & Visitors > Health Library > Prediabetes
Prediabetes is a warning sign that you are at risk for getting type 2 diabetes. It means that your blood sugar is higher than it should be, but not high enough to be diabetes. Prediabetes is also called impaired glucose tolerance or impaired fasting glucose. Most people who get type 2 diabetes have prediabetes first.
The food you eat turns into sugar, which your body uses for energy. Normally, an organ called the pancreas makes insulin, which allows the sugar in your blood to get into your body's cells. But when your body can't use insulin the right way, the sugar doesn't move into cells. It stays in your blood instead. This is called insulin resistance. The buildup of sugar in the blood causes prediabetes.
People who are overweight, aren't physically active, and have a family history of diabetes are more likely to get prediabetes. Women who have had gestational diabetes are also more likely to get prediabetes.
Most people with prediabetes don't have any symptoms. But if you have prediabetes, you need to watch for signs of diabetes, such as:
A blood test can tell if you have prediabetes. You have prediabetes if:
The key to treating prediabetes and preventing type 2 diabetes is getting your blood sugar levels back to a normal range. You can do this by making some lifestyle changes.
Making these changes may help delay or prevent diabetes. You may also avoid or delay some of the serious problems that you can get when you have diabetes, such as heart attack, stroke, and heart, eye, nerve, and kidney disease.
You may need to take a diabetes medicine called metformin. It reduces the amount of sugar made by the liver in people who are insulin-resistant.
Staying at a healthy weight, eating healthy foods, and getting regular exercise can help prevent prediabetes.
Health Tools help you make wise health decisions or take action to improve your health.
Prediabetes occurs when your body isn't able to keep your sugar (glucose) at a normal level in your blood. Your blood sugar is higher than normal, but it's not high enough to be diabetes.
The food you eat turns into sugar, which your body uses for energy. Normally, the pancreas makes insulin, which allows the sugar in blood to get into the body's cells. But when your body can't use insulin the right way, the sugar doesn't move into cells. It stays in your blood instead. This is called insulin resistance.
The buildup of sugar in the blood causes prediabetes. If your blood sugar stays too high for too long, prediabetes can turn into type 2 diabetes.
Most of the time, prediabetes has no symptoms. But if you have prediabetes, you need to watch for signs of type 2 diabetes, such as:
Prediabetes is a warning sign that you are at risk for getting type 2 diabetes.
When you have prediabetes, you're also at higher risk for eye, nerve, kidney and heart disease, and for stroke. For more information on these complications, see the topic Type 2 Diabetes.
One Man's Story:
When he first found out he had prediabetes, Jerry felt angry and frustrated. His doctor told him to lose weight and get more exercise, or else run the risk of getting type 2 diabetes.
"I thought, 'What's the point? I might still get diabetes.' I felt like I was stuck either way. But it turns out there's a lot you can do."— Jerry
Read more about Jerry.
You can reduce your risk for type 2 diabetes and related health problems by making healthy lifestyle changes, such as:
For more information, see Prevention.
Things that can increase your chances of prediabetes are called risk factors. Some risk factors you can control, and others you can't.
The risk factors for prediabetes are similar to those for type 2 diabetes. Most people who get type 2 diabetes had prediabetes first. Risk factors include:
Other health problems that put you at risk for prediabetes and type 2 diabetes include:
One Woman's Story:
With a family history of type 2 diabetes, Linda says she should have watched her weight more carefully. She wasn't too surprised by her prediabetes diagnosis. But she got motivated right away to do what she could about it.
"I watched my mom inject herself with insulin every day. Sometimes she needed my help. She had the hardest time keeping her blood sugar down and figuring out what to eat. I don't want to go down that road if I can help it."— Linda
Read more about Linda.
There are some things you can do to reduce your chances of getting prediabetes:
When you have prediabetes, it's important to follow your treatment. This can reduce your risk of prediabetes turning into type 2 diabetes.
For more tips about things you can do to reduce your risk, see Prevention.
When you have prediabetes, it's important to watch for symptoms of type 2 diabetes. Call your doctor if you notice that you are:
You may want to talk to your doctor about testing for prediabetes if you are:
Your doctor will do a medical history, a physical exam, and blood glucose testing to find out if you have prediabetes and are at risk for getting type 2 diabetes.
Blood tests used to identify prediabetes in adults include:
You have prediabetes if:
Phrases such as "a touch of diabetes," "borderline diabetes," and "your sugar is a little high" are unclear. If you hear these phrases, ask your doctor if your blood sugar level is in the prediabetes or diabetes range.
Tests for other health problems
If you are diagnosed with prediabetes, your doctor may also want to:
Your treatment for prediabetes will focus on losing weight, eating healthy foods, and getting active. This is your chance to reverse prediabetes so it doesn't turn into type 2 diabetes. Doing these things will also help you avoid other health problems, such as heart disease and stroke, that are linked to diabetes.
You may also need to take diabetes medicine along with doing these things.
Most people who have prediabetes are overweight and have a body mass index (BMI) of 25 or higher. To find out your BMI, use the Interactive Tool: Is Your BMI Increasing Your Health Risks?
If you have a BMI of 25 or higher, try to lose 7% to 10% of your body weight. For example, if you weigh 200 pounds, aim to lose 14 to 20 pounds.
A healthy weight helps your body use insulin the way it should. Losing weight can also lower insulin resistance in people who have prediabetes. The more you lose, the more you benefit, as long as you do it in a healthy way.
How you do it is up to you. One way to start is by making healthy eating changes that you can keep doing over time. Try reducing the number of calories you eat and drink and adding more activity to your day. For help, see the topic Weight Management.
Jerry signed up for a weight-loss program and started a daily food diary to track what and when he ate. He added walks around the neighborhood and visits to the gym to his routine. In 7 months, he dropped 25 pounds—about 10% of his body weight.
"It hasn't been easy. I've had some ups and downs, especially over the holidays. Hey, I love to eat. Sometimes it's hard to stay focused. But tracking what, when, and why I eat helps me to eat less."— Jerry
Eating a balanced diet is one of the best things you can do for yourself and for your health. Try to:
For help, see the topic Healthy Eating.
The more active you are, the more sugar (glucose) your body uses for energy. This keeps the sugar from building up in your blood. Exercise can also improve insulin resistance.
Try to do moderate activity at least 2½ hours a week. Or try to do vigorous activity at least 1¼ hours a week. It's fine to be active in blocks of 10 minutes or more throughout your day and week.
Moderate activity is safe for most people, but it's always a good idea to talk to your doctor before you start an exercise program. For more help, see the topic Fitness.
Linda works full-time, has three young children, and has zero time for the gym. So when she learned she had prediabetes, she had to find creative ways to fit activity into her day. For example, after dinner she turns up the stereo and does dance moves while washing dishes, putting food away, and cleaning the kitchen.
"It takes about a half-hour and is a great workout. My kids get a big kick out of it too."— Linda
Read more about Linda.
You may need to take an oral medicine, such as metformin. It reduces the amount of sugar made by the liver in people who are insulin resistant.
If you do need medicine, be sure to take it as directed.
Quitting smoking might help you reduce your risk for type 2 diabetes and heart disease and also might help you avoid other health problems that make diabetes worse. Quitting can also reduce your risk of heart attack and stroke. For more information, see the topic Quitting Smoking.
When you have prediabetes, you are more likely to get heart disease than someone who has normal blood sugar levels. Your risk of having heart disease is even higher if you have high blood pressure or high cholesterol. That is why it's important to have a heart-healthy lifestyle. This includes preventing or managing high blood pressure and high cholesterol.
Even if you have risk factors for prediabetes, you can still take steps to prevent the disease. And if you already have prediabetes, these same steps can keep it from turning into type 2 diabetes.
Your risk for prediabetes is higher if you are overweight and physically inactive. So:
Prediabetes is a warning sign that you are at risk for type 2 diabetes. But you can make the healthy changes needed to prevent it.
Losing weight, getting active, and eating better are all important changes you can make for your health. These are the best things you can do to prevent prediabetes or to stop it from turning into type 2 diabetes. Three steps can help you get started.
1. Know your reason. Before you set a goal, think about why you want to make a change. If your reason comes from you—and not from someone else—it will be easier for you to make a healthy change for good.
Maybe you want to avoid the hassles that come with type 2 diabetes, such as taking insulin or testing blood sugar. Or maybe you are worried about the health problems diabetes brings. You might simply want to enjoy your life and have more energy. Your reason for wanting to change is important.
2. Set long-term and short-term goals. Start by setting a big, or long-term, goal. Maybe you want to lose 10% of your body weight to reduce your risk of type 2 diabetes. If you weigh 200 pounds, that means losing 20 pounds. Break down your big goal into smaller, short-term goals. These are the steps you'll take to reach your big goal.
Do what works best for you. It's important to set goals you can reach. For example:
3. Prepare for slip-ups and barriers. Plan for setbacks. Use a personal action plan to write down your goals, any possible barriers, and your ideas for getting past them. By thinking about these barriers now, you can plan ahead for how to deal with them if they happen.
Your doctor may prescribe metformin (Glucophage). If you need medicine, your doctor is most likely to prescribe this one. Metformin reduces how much glucose the liver makes. It can also lower insulin resistance.
Talk with your doctor to find out if you need medicine in addition to lifestyle changes to lower your insulin resistance.
Other Works Consulted
Buse JB (2011). Type 2 diabetes mellitus. In S Melmed et al., eds., Williams Textbook of Endocrinology, 12th ed., pp. 1371–1435. Philadelphia: Saunders.
Diabetes Prevention Resource Group (2002). Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. New England Journal of Medicine, 846(6): 393–403.
McCall AL (2015). Diabetes mellitus in adults. In ET Bope, RD Kellerman, eds., Conn's Current Therapy 2015, pp. 736–745. Philadelphia: Saunders.
Schellenberg ES, et al. (2013). Lifestyle interventions for patients with and at risk for type 2 diabetes: A systematic review and meta-analysis. Annals of Internal Medicine, 159(8): 543–551. DOI: 10.7326/0003-4819-159-8-201310150-00007. Accessed November 25, 2013.
Current as of:
December 20, 2019
Author: Healthwise StaffMedical Review: E. Gregory Thompson MD - Internal MedicineKathleen Romito MD - Family MedicineAdam Husney MD - Family MedicineDavid C.W. Lau MD, PhD, FRCPC - Endocrinology
Current as of: December 20, 2019
Author: Healthwise Staff
Medical Review:E. Gregory Thompson MD - Internal Medicine & Kathleen Romito MD - Family Medicine & Adam Husney MD - Family Medicine & David C.W. Lau MD, PhD, FRCPC - Endocrinology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2020 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.