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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
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.
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
stroke, and heart, eye, nerve, and kidney
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
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Learning about prediabetes:
Living with prediabetes:
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
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.
People who are overweight, aren't physically active, and have a
family history of diabetes are more likely to get prediabetes. Women who have
gestational diabetes are also more likely to get
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:
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
Read more about Jerry.
You can reduce your risk for type 2 diabetes and
related health problems by making healthy lifestyle changes, such
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
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
"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
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 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.
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
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
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
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
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.
moderate activity at least 2½ hours a week. Or try to
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
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
"It takes about a half-hour and is a great workout. My
kids get a big kick out of it too."—Linda
need to take an oral medicine, such as
metformin. It reduces the amount
of sugar made by the
liver in people who are
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.
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.
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
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
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(What is a PDF document?) 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
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
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.
McCall AL (2015). Diabetes mellitus in adults. In ET Bope, RD Kellerman, eds., Conn's Current Therapy 2015, pp. 736–745. Philadelphia: Saunders.
Riddle MC, Genuth S (2010). Type 2 diabetes mellitus. In EG Nabel, ed., ACP Medicine, section 9, chap. 2. Hamilton, ON: BC Decker.
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.
ByHealthwise StaffPrimary Medical ReviewerE. Gregory Thompson, MD - Internal MedicineKathleen Romito, MD - Family MedicineAdam Husney, MD - Family MedicineSpecialist Medical ReviewerDavid C.W. Lau, MD, PhD, FRCPC - Endocrinology
Current as ofSeptember 20, 2016
Current as of:
September 20, 2016
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.
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