Millions of Us Are 'Pre-Diabetic'

The number of Americans who should think seriously about diabetes has nearly doubled. About 18 million Americans have been diagnosed with diabetes, about 17 million of them have type 2 diabetes.

But there's a new group, experts say, that needs to act. The American Diabetes Association estimates at least 20.1 million people in the United States (21.1% of the population), ages 40 to 74, have pre-diabetes. Pre-diabetes is also known as imparied glucose tolerance, means having a blood sugar level that is higher than normal, but not yet persistently high enough to be considered type 2 diabetes. By taking steps to control your blood sugar, even if you have pre-diabetes, you can delay or prevent type 2 diabetes from developing.

"The vast majority of [people with pre-diabetes] are 40 and older," says Frank Vinicor, M.D., M.P.H., diabetes program director at the Centers for Disease Control and Prevention (CDC).

If you have pre-diabetes, you are at 50 percent higher risk for developing heart disease and stroke. According to the ADA, risk factors for pre-diabetes include:

• Being overweight or obese; a body mass index (BMI) of 25 to 29.9 is considered overweight, and a BMI of 30 or higher is obese

• A family history of type 2 diabetes

• Being an African American, American Indian, Hispanic American or Asian American

• Low HDL cholesterol and high triglycerides

• High blood pressure

• A history of gestational diabetes

"These are people who are likely to get type 2, or adult onset, diabetes if they don't change the way they live," says Dr. Vinicor. Here are the types of changes experts suggest:

• Weight loss

• Healthy diet

• Moderate exercise

"We've found that losing 8 to 10 pounds can make a difference," Dr. Vinicor says. "People shouldn't think they can't help themselves because they can't lose a large amount at once." You should aim for a BMI of 27 -- ideally, 25 or less.

"To lose weight, maintain loss and live a healthier life, we recommend 150 minutes of exercise a week," Dr. Vinicor says. "That might sound like a lot, but it can be 30 minutes of walking, five times a week."

The goal is to prevent most pre-diabetics from developing diabetes and to ensure that those who develop diabetes do so later in life. "We'd like to see 40- to 45-year-olds and older folks begin to be more thoughtful about this and to ask their family doctor about it," Dr. Vinicor adds.

By the numbers

Two types of tests can determine whether you have pre-diabetes: fasting plasma glucose test (FPG) or the oral glucose tolerance test (OGTT). If your blood sugar level is abnormal with the FPG, you have impaired fasting glucose, according to the ADA. If your blood sugar level is abnormal with the OGTT, you have impaired glucose tolerance.

Here's what overnight fasting blood sugar numbers (with eight hours or more of fasting) mean, according to CDC guidelines backed by the National Institutes of Health, Department of Health and Human Services and American Diabetes Association. Doctors measure blood sugar in milligrams per deciliter (mg/dl):

• Normal: Below 100 mg/dl

• Pre-diabetes: 100-125 mg/dl

• Diabetes: 126 mg/dl and above

Here is what oral glucose tolerance blood sugar numbers mean, according to the ADA:

• Normal: Below 140 mg/dl

• Pre-diabetes: 140-199 mg/dl

• Diabetes: 200 mg/dl and above