Am I at Risk for Type 2 Diabetes?
Taking Steps to Lower Your Risk of Getting Diabetes
On this page:
- What is type 2 diabetes?
- Can type 2 diabetes be delayed or prevented?
- Other Types of Diabetes
- What are the signs and symptoms of type 2 diabetes?
- Should I be tested for diabetes and prediabetes?
- What does having prediabetes mean?
- What factors increase my risk for type 2 diabetes?
- Does sleep matter?
- How can I reduce my risk for type 2 diabetes?
- Making Changes to Lower My Risk
- Eating, Diet, and Nutrition
- Measure Your Waist
- Body Mass Index (BMI)
- Hope through Research
- For More Information
What is type 2 diabetes?
Type 2 diabetes, formerly called adult-onset diabetes, is the most common type of diabetes. About 95 percent of people with diabetes have type 2. People can develop type 2 diabetes at any age, even during childhood. However, this type of diabetes develops most often in middle-aged and older people. People who are overweight and inactive are also more likely to develop type 2 diabetes.
In type 2 and other types of diabetes, you have too much glucose, also called sugar, in your blood. People with diabetes have problems converting food to energy. After a meal, food is broken down into glucose, which is carried by your blood to cells throughout your body. With the help of the hormone insulin, cells absorb glucose from your blood and use it for energy. Insulin is made in the pancreas, an organ located behind the stomach.
Type 2 diabetes usually begins with insulin resistance, a condition linked to excess weight in which your body’s cells do not use insulin properly. As a result, your body needs more insulin to help glucose enter cells. At first, your pancreas keeps up with the added demand by producing more insulin. But in time, your pancreas loses its ability to produce enough insulin, and blood glucose levels rise.
Over time, high blood glucose damages nerves and blood vessels, leading to problems such as heart disease, stroke, kidney disease, blindness, dental disease, and amputations. Other problems of diabetes may include increased risk of getting other diseases, loss of mobility with aging, depression, and pregnancy problems.
Treatment includes taking diabetes medicines, making wise food choices, being physically active on a regular basis, controlling blood pressure and cholesterol, and for some, taking aspirin daily.
Can type 2 diabetes be delayed or prevented?
Yes. The results of the Diabetes Prevention Program (DPP) proved that weight loss through moderate diet changes and physical activity can delay or prevent type 2 diabetes. The DPP was a federally funded study of 3,234 people at high risk for diabetes. This study showed that a 5-to 7-percent weight loss, which for a 200-pound person would be 10 to 14 pounds, slowed development of type 2 diabetes.
People at High Risk for Diabetes
DPP study participants were overweight and had higher than normal levels of blood glucose, a condition called prediabetes. Many had family members with type 2 diabetes. Prediabetes, obesity, and a family history of diabetes are strong risk factors for type 2 diabetes. About half of the DPP participants were from minority groups with high rates of diabetes, including African Americans, Alaska Natives, American Indians, Asian Americans, Hispanics/Latinos, and Pacific Islander Americans.
DPP participants also included others at high risk for developing type 2 diabetes, such as women with a history of gestational diabetes and people age 60 and older.
Approaches to Preventing Diabetes
The DPP tested three approaches to preventing diabetes:
- Making lifestyle changes. People in the lifestyle change group exercised, usually by walking 5 days a week for about 30 minutes a day, and lowered their intake of fat and calories.
- Taking the diabetes medicine metformin. Those who took metformin also received information about physical activity and diet.
- Receiving education about diabetes. The third group only received information about physical activity and diet and took a placebo—a pill without medicine in it.
People in the lifestyle change group showed the best outcomes. But people who took metformin also benefited. The results showed that by losing an average of 15 pounds in the first year of the study, people in the lifestyle change group reduced their risk of developing type 2 diabetes by 58 percent over 3 years. Lifestyle change was even more effective in those age 60 and older. People in this group reduced their risk by 71 percent. But people in the metformin group also benefited, reducing their risk by 31 percent. More information about the DPP, funded under National Institutes of Health (NIH) clinical trial number NCT00004992, is available at www.bsc.gwu.edu/dpp .
The Diabetes Prevention Program Outcomes Study (DPPOS) has shown that the benefits of weight loss and metformin last for at least 10 years. The DPPOS has continued to follow most DPP participants since the DPP ended in 2001. The DPPOS showed that 10 years after enrolling in the DPP,
- people in the lifestyle change group reduced their risk for developing diabetes by 34 percent
- those in the lifestyle change group age 60 or older had even greater benefit, reducing their risk of developing diabetes by 49 percent
- participants in the lifestyle change group also had fewer heart and blood vessel disease risk factors, including lower blood pressure and triglyceride levels, even though they took fewer medicines to control their heart disease risk
- the metformin group reduced the risk of developing diabetes by 18 percent
Even though controlling your weight with lifestyle changes is challenging, it produces long-term health rewards by lowering your risk for type 2 diabetes, lowering your blood glucose levels, and reducing other heart disease risk factors. More information about the DPPOS, funded under NIH clinical trial number NCT00038727, can be found at www.bsc.gwu.edu/dpp .
What are the signs and symptoms of type 2 diabetes?
The signs and symptoms of type 2 diabetes can be so mild that you might not even notice them. Nearly 7 million people in the United States have type 2 diabetes and don’t know they have the disease. Many have no signs or symptoms. Some people have symptoms but do not suspect diabetes.
- increased thirst
- increased hunger
- increased urination, especially at night
- unexplained weight loss
- blurred vision
- numbness or tingling in the feet or hands
- sores that do not heal
Many people do not find out they have the disease until they have diabetes problems, such as blurred vision or heart trouble. If you find out early that you have diabetes, you can get treatment to prevent damage to your body.
Should I be tested for diabetes and prediabetes?
Anyone 45 years of age or older should consider getting tested for diabetes and prediabetes. If you are 45 or older and overweight—see the body mass index (BMI) chart—getting tested is strongly recommended. If you are younger than 45, overweight, and have one or more other risk factors, you should consider getting tested. Ask your doctor for an A1C test, a fasting blood glucose test, or an oral glucose tolerance test.
Your doctor will tell you if you have normal blood glucose, diabetes, or prediabetes. If you are told you have prediabetes, take steps to prevent type 2 diabetes. And ask your doctor if you should be tested again in 1 year.
What does having prediabetes mean?
Having prediabetes means your blood glucose is higher than normal but not high enough to be diagnosed as diabetes. In 2009, at least 78 million American adults were estimated to have prediabetes. Having prediabetes also means you are at risk for getting type 2 diabetes and heart disease. However, you can reduce your risk of getting diabetes and even return blood glucose levels to normal by losing a little weight through healthy eating and being more physically active.[Top]
What factors increase my risk for type 2 diabetes?
To find out your risk for type 2 diabetes, check each item that applies to you.
- I am age 45 or older.
- I am overweight or obese.
- I have a parent, brother, or sister with diabetes.
- My family background is African American, Alaska Native, American Indian, Asian American, Hispanic/Latino, or Pacific Islander American.
- I have had gestational diabetes.
- I gave birth to at least one baby weighing more than 9 pounds.
- My blood pressure is 140/90 or higher, or I have been told that I have high blood pressure.
- My cholesterol levels are higher than normal. My HDL, or good, cholesterol is below 35, or my triglyceride level is above 250.
- I am fairly inactive.
- I have polycystic ovary syndrome, also called PCOS.
- On previous testing, I had prediabetes—an A1C level of 5.7 to 6.4 percent, impaired fasting glucose (IFG), or impaired glucose tolerance (IGT).
- I have other clinical conditions associated with insulin resistance, such as a condition called acanthosis nigricans, characterized by a dark, velvety rash around my neck or armpits.
- I have a history of cardiovascular disease.
The more items you checked, the higher your risk.
How can I reduce my risk for type 2 diabetes?
You can do a lot to reduce your risk of getting type 2 diabetes. Being more physically active, reducing fat and calorie intake, and losing a little weight can help you lower your chances of developing type 2 diabetes. Taking the diabetes medicine metformin can also reduce risk, particularly in younger and heavier people with prediabetes and women who have had gestational diabetes. Lowering blood pressure and cholesterol levels also helps you stay healthy.
If you are overweight, then take these steps:
- Reach and maintain a reasonable body weight. Even a 10 or 15 pound weight loss makes a big difference.
- Make wise food choices most of the time.
- Be physically active every day.
If you are fairly inactive, then take this step:
If your blood pressure is too high, then take these steps:
- Reach and maintain a reasonable body weight.
- Make wise food choices most of the time.
- Reduce your sodium and alcohol intake.
- Be physically active every day.
- Talk with your doctor about whether you need medicine to control your blood pressure.
If your cholesterol or triglyceride levels are too high, then take these steps:
- Make wise food choices most of the time.
- Be physically active every day.
- Talk with your doctor about whether you need medicine to control your cholesterol levels.
Making Changes to Lower My Risk
Making big changes in your life is hard, especially if you are faced with more than one change. You can make it easier by taking these steps:
- Make a plan to change behavior.
- Decide exactly what you will do and give yourself a time frame.
- Plan what you need to get ready.
- Track your goals and activity on a food and activity tracker, available at www.ndep.nih.gov/media/gp_foodacttracker.pdf (PDF, 349 KB) *
- Think about what might prevent you from reaching your goals.
- Find family and friends who will support and encourage you.
- Decide how you will reward yourself—a shopping trip, movie tickets, an afternoon in the park—when you do what you have planned.
Your doctor, a dietitian, or a counselor can help you make a plan.
Be Physically Active Every Day
Regular physical activity tackles several risk factors at once. Activity helps you lose weight; keeps your blood glucose, blood pressure, and cholesterol under control; and helps your body use insulin. People in the DPP who were physically active for 30 minutes a day, 5 days a week, reduced their risk of type 2 diabetes. Many chose brisk walking as their physical activity.
If you are not fairly active, you should start slowly. First, talk with your doctor about what kinds of physical activity are safe for you. Make a plan to increase your activity level toward the goal of being active at least 30 minutes a day most days of the week. You can increase your level of physical activity in two main ways:
1. Start an exercise program.
2. Increase your daily activity.
Start an exercise program. Pick exercises that suit you. Find a friend to walk with you or join an exercise class that will help you keep going.
- Do aerobic activities, which use your large muscles to make your heart beat faster. The large muscles are those of the upper and lower arms; upper and lower legs; and those that control head, shoulder, and hip movements.
- Do activities to strengthen muscles and bone, such as lifting weights or sit-ups, two to three times a week. Find help—such as a video or a class—to learn how to do these exercises properly.
Increase your daily activity. Choose activities you enjoy. You can work extra activity into your daily routine by doing the following:
- Increase daily activity by decreasing time spent watching TV or at the computer. Set up a reminder on your computer to take an activity break.
- Take the stairs rather than an elevator or escalator.
- Park at the far end of the parking lot and walk.
- Get off the bus a few stops early and walk the rest of the way.
- Walk or bicycle whenever you can.
Take Your Prescribed Medicines
Some people need medicine to help control their blood pressure or cholesterol levels. If you do, take your medicines as directed. Ask your doctor if you should take metformin to prevent type 2 diabetes. Metformin is a medicine that makes insulin work better and can reduce the risk of type 2 diabetes.
Eating, Diet, and Nutrition
Your eating, diet, and nutrition choices play an important role in preventing or delaying diabetes. Follow the suggestions below to reach and maintain a reasonable weight and make wise food choices most of the time. Remember that it can take time to change your habits and be patient with yourself. You can also get help from a dietitian or join a weight-loss program to support you while you reach your goals.
Reach and Maintain a Reasonable Body Weight
Your weight affects your health in many ways. Being overweight can keep your body from making and using insulin properly. Excess body weight can also cause high blood pressure. Every pound you lose lowers your risk of getting diabetes.
In addition to weight, the location of excess fat on the body can be important. A waist measurement of 40 inches or more for men and 35 inches or more for women is linked to insulin resistance and increases a person’s risk for type 2 diabetes. This is true even if your BMI falls within the normal range.
Find Your BMI
The BMI is a measure of body weight relative to height. The BMI can help you find out whether you are normal weight, overweight, or obese. Use the table on pages 24 and 25 to find your BMI.
- Find your height in the left-hand column.
- Move across in the same row to the number closest to your weight.
- The number at the top of that column is your BMI. Check the word above your BMI to see whether you are normal weight, overweight, or obese.
The BMI has certain limitations. The BMI may overestimate body fat in athletes and others who have a muscular build and underestimate body fat in older adults and others who have lost muscle.
The BMI for children and teens must be determined based on age, height, weight, and sex. The Centers for Disease Control and Prevention (CDC) has information about BMI in children and teens, including a BMI calculator, at www.cdc.gov/nccdphp/dnpa/bmi. The CDC website also has a BMI calculator for adults. A BMI calculator from the NIH is available at www.nhlbisupport.com/bmi .
The NIH also has a free smartphone app for calculating BMI. You can search “My BMI Calculator” on your phone to find the app. The app also provides links to information about steps you can take to bring your BMI into a healthy range.
Body Mass Index TableFor a printer-friendly version of this table, use the pdf. (PDF, 34 KB) *
|Body Weight (pounds)|
|Body Weight (pounds)|
If you are overweight or obese, choose sensible ways to get in shape:
- Avoid crash diets. Instead, eat less of the foods you usually have. Limit the amount of fat you eat.
- Increase your physical activity. Aim for at least 30 minutes of physical activity most days of the week.
- Set a reasonable weight-loss goal, such as losing 1 pound a week. Aim for a long-term goal of losing 5 to 7 percent of your total body weight. To estimate this amount in pounds, find the weight closest to yours on the chart below. Follow the row across to see how many pounds you need to lose.
|Your weight in pounds||5 percent loss in pounds||7 percent loss in pounds|
To find your exact weight loss goal, multiply .05 by your weight in pounds to find your 5 percent goal; multiply .07 by your weight to find your 7 percent goal.
Make Wise Food Choices Most of the Time
What you eat has a big effect on your health. By making wise food choices, you can help control your body weight, blood glucose, blood pressure, and cholesterol.
- Take a look at the serving sizes of the foods you eat. Reduce serving sizes of main courses, meat, desserts, and other foods high in fat. Increase the amount of fruits and vegetables you eat at every meal. Try using a small plate. For more help with choosing serving sizes, see the United States Department of Agriculture's website at www.choosemyplate.gov.
- Limit your fat intake to about 25 percent of your total calories. For example, if your food choices add up to about 2,000 calories a day, try to eat no more than 56 grams of fat. Your doctor or a dietitian can help you figure out how much fat to have. You can also check food labels for fat content.
- Limit your sodium intake to less than 2,300 milligrams—about 1 teaspoon of salt—each day.
- Talk with your doctor about whether you may drink alcoholic beverages. If you choose to drink alcoholic beverages, limit your intake to one drink for women or two drinks for men per day.
- You may also wish to reduce the number of calories you have each day. People in the DPP lifestyle change group lowered their daily calorie total by an average of about 450 calories. Your doctor or dietitian can help you with a healthy eating plan that emphasizes weight loss.
- Keep a food and physical activity log. Write down what you eat and how much physical activity you are getting. People who keep track are more successful in losing weight.
- When you meet your goal, reward yourself with a nonfood item or activity, such as watching a movie.
Vitamin D studies show a link between people’s ability to maintain healthy blood glucose levels and having enough vitamin D in their blood. However, studies to determine the proper vitamin D levels for people with diabetes and for preventing diabetes are ongoing; no special recommendations have been made about vitamin D levels or supplements for people with diabetes.
Currently, the Institute of Medicine (IOM), the agency that recommends supplementation levels based on current science, provides the following guidelines for daily vitamin D intake:
- People ages 1 to 70 years may require 600 International Units (IUs)
- People age 71 and older may require as much as 800 IUs
The IOM also recommended that no more than 4,000 IUs of vitamin D be taken per day.
To help ensure coordinated and safe care, you should discuss your use of complementary and alternative medicine practices, including your use of dietary supplements, with your doctor.
More information about using dietary supplements to help with diabetes is available from the National Diabetes Information Clearinghouse at www.diabetes.niddk.nih.gov/dm/pubs/alternativetherapies/index.aspx.
Hope through Research
The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) conducts and supports research related to the causes, treatment, and prevention of diabetes. For example, clinical trials include The Avoiding Diabetes Thru Action Plan Targeting Pilot Randomized Control Trial (ADAPT). This trial is an innovative study that uses technology to affect lifestyle behavior change. This study is funded under NIH clinical trial number NCT01473654.
We now know that many people can delay or prevent type 2 diabetes through weight loss, regular physical activity, and lowering their intake of fat and calories. Researchers are working hard to understand the genetic and environmental factors that contribute to a person’s tendency to develop obesity, diabetes, and prediabetes. As researchers learn more about the molecular events that lead to diabetes, they will develop ways to prevent and cure different stages of this disease. Already, the DPP has shown that even in participants at higher genetic risk for type 2 diabetes, losing weight through lifestyle change lowered the risk of diabetes. DPP researchers continue to monitor DPP participants through the DPPOS to learn more about the study’s long-term effects.
Participants in clinical trials can play a more active role in their own health care, gain access to new research treatments before they are widely available, and help others by contributing to medical research. For more information about current studies, visit www.ClinicalTrials.gov.[Top]
For More Information
More information about insulin resistance, the DPP, and how to lower your risk for type 2 diabetes is available in the following publications:
- Insulin Resistance and Prediabetes
- Diabetes Prevention Program (DPP)
These publications are available at www.diabetes.niddk.nih.gov or by calling 1–800–860–8747.
As part of its Small Steps. Big Rewards. Prevent type 2 Diabetes campaign, the National Diabetes Education Program (NDEP) offers several booklets about preventing type 2 diabetes, including information about setting goals, tracking progress, implementing a walking program, and finding additional resources. These materials are available at www.ndep.nih.gov or by calling the NDEP at 1–888–693–NDEP (1–888–693–6337).Top]
Publications produced by the Clearinghouse are carefully reviewed by both NIDDK scientists and outside experts. This publication was originally reviewed by David G. Marrero, Ph.D., Indiana University School of Medicine, Diabetes Research and Training Center, and Michael L. Parchman, M.D., M.P.H., associate professor, Department of Family and Community Medicine, University of Texas Health Science Center.
National Diabetes Education Program
1 Diabetes Way
Bethesda, MD 20814–9692
Phone: 1–888–693–NDEP (1–888–693–6337)
The National Diabetes Education Program is a federally funded program sponsored by the U.S. Department of Health and Human Services’ National Institutes of Health and the Centers for Disease Control and Prevention and includes over 200 partners at the federal, state, and local levels, working together to reduce the morbidity and mortality associated with diabetes.
National Diabetes Information Clearinghouse
The National Diabetes Information Clearinghouse (NDIC) is a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). The NIDDK is part of the National Institutes of Health of the U.S. Department of Health and Human Services. Established in 1978, the Clearinghouse provides information about diabetes to people with diabetes and to their families, health care professionals, and the public. The NDIC answers inquiries, develops and distributes publications, and works closely with professional and patient organizations and Government agencies to coordinate resources about diabetes.
This publication is not copyrighted. The Clearinghouse encourages users of this publication to duplicate and distribute as many copies as desired.
This publication may contain information about medications. When prepared, this publication included the most current information available. For updates or for questions about any medications, contact the U.S. Food and Drug Administration toll-free at 1-888-INFO-FDA (1-888-463-6332) or visit www.fda.gov. Consult your health care provider for more information.
NIH Publication No 12-4805
Page last updated: July 23, 2012