The Diabetes Prevention Program (DPP), a major federally funded study of 3,234 people at high risk for diabetes, showed that people can delay and possibly prevent the disease by losing a small amount of weight (5 to 7 percent of total body weight) through 30 minutes of physical activity 5 days a week and healthier eating.

For more information, see the National Diabetes Education Program’s Small Steps. Big Rewards. Prevent Type 2 Diabetes Campaign

When should I be tested for diabetes?

Anyone aged 45 years or older should consider getting tested for diabetes, especially if you are overweight. If you are younger than 45, but are overweight and have one or more additional risk factors (see below), you should consider testing.

What are the risk factors which increase the likelihood of developing diabetes?

Being overweight or obese

A parent, brother, or sister with diabetes

African American, American Indian, Asian American, Pacific Islander, or Hispanic American/Latino heritage

Prior history of gestational diabetes or birth of at least one baby weighing more than 9 pounds

High blood pressure measuring 140/90 or higher

Abnormal cholesterol with HDL ("good") cholesterol is 35 or lower, or triglyceride level is 250 or higher

Physical inactivity—exercising fewer than three times a week

For more information, see the National Diabetes Information Clearinghouse’s Am I at Risk for Type 2 Diabetes?

How does body weight affect the likelihood of developing diabetes?

Being overweight or obese is a leading risk factor for type 2 diabetes. Being overweight can keep your body from making and using insulin properly, and can also cause high blood pressure. The Diabetes Prevention Program (DPP), a major federally funded study of 3,234 people at high risk for diabetes, showed that moderate diet and exercise of about 30 minutes or more, 5 or more days per week, or of 150 or more minutes per week, resulting in a 5% to 7% weight loss can delay and possibly prevent type 2 diabetes.

What is pre-diabetes?

People with blood glucose levels that are higher than normal but not yet in the diabetic range have "pre-diabetes." Doctors sometimes call this condition impaired fasting glucose (IFG) or impaired glucose tolerance (IGT), depending on the test used to diagnose it. Insulin resistance and pre-diabetes usually have no symptoms. You may have one or both conditions for several years without noticing anything.

If you have pre-diabetes, you have a higher risk of developing type 2 diabetes. Studies have shown that most people with pre-diabetes go on to develop type 2 diabetes within 10 years, unless they lose weight through modest changes in diet and physical activity. People with pre-diabetes also have a higher risk of heart disease.

For more information, see:

The Center for Disease Control and Prevention’s National Diabetes Fact Sheet 2003
The National Diabetes Information Clearinghouse’s Insulin Resistance and Pre-Diabetes
The American Diabetes Association’s Frequently Asked Questions About Pre-Diabetes*

Can vaccines cause diabetes?

No. Carefully performed scientific studies show that vaccines do not cause diabetes or increase a person’s risk of developing diabetes. In 2002, the Institute of Medicine reviewed the existing studies and released a report concluding that the scientific evidence favors rejection of the theory that immunizations cause diabetes. The only evidence suggesting a relationship between vaccination and diabetes comes from Dr. John B. Classen, who has suggested that certain vaccines if given at birth may decrease the occurrence of diabetes, whereas if initial vaccination is performed after 2 months of age the occurrence of diabetes increases. Dr. Classen's studies have a number of limitations and have not been verified by other researchers.

For more information, visit:

The CDC National Immunization Program’s Diabetes and Vaccines
The Juvenile Diabetes Research Foundation International’s Statement Regarding Type 1 Diabetes and Vaccines*
The Journal of the American Medical Association’s Vaccines Pose No Diabetes, Bowel Disease Risk*

* Links to non-Federal organizations are provided solely as a service to our users. Links do not constitute an endorsement of any organization by CDC or the Federal Government, and none should be inferred. The CDC is not responsible for the content of the individual organization Web pages found at this link.

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Page last reviewed: December 3, 2008
Page last modified: June 27, 2006
Content Source: National Center for Chronic Disease Prevention and Health Promotion
Division of Diabetes Translation

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