Type 2 Diabetes and Impaired Fasting Glucose

What is type 2 diabetes? What is impaired fasting glucose?

Diabetes is a disease that occurs when a person's body doesn't make enough insulin or can't use insulin properly. If left untreated, it may result in blindness, heart attacks, strokes, kidney failure and amputations. There are two types of diabetes. Type 1 occurs when the body doesn't produce any insulin. People with type 2 diabetes either don't produce enough insulin or their cells ignore the insulin. Nearly 95% of people with diabetes have type 2.

Before people get type 2 diabetes, they usually have impaired fasting glucose (IFG). In people who have IFG, blood sugar levels are higher than normal but not high enough to say they have diabetes. People who have IFG have a high risk of getting diabetes. They also are more likely to have a heart attack.

How can my doctor tell if I have impaired fasting glucose or diabetes?

Your doctor can use a blood test to see if you have IFG or diabetes.

Who is at risk?

You are at risk for getting IFG or diabetes if any of the following are true:

  • You are overweight or obese.
  • You have a parent, brother or sister who has diabetes.
  • You had diabetes during pregnancy (called gestational diabetes) or had a baby who weighed more than 9 pounds at birth.
  • You belong to any of the following ethnic groups: African American, Native American, Latin American or Asian/Pacific Islander.
  • You have high blood pressure (above 140/90 mm Hg).
  • Your high-density lipoprotein (HDL) cholesterol level (“good” cholesterol) is less than 40 mg per dL (for men) or less than 50 mg per dl (for women), or your triglyceride level is higher than 250 mg per dL.

What can I do to avoid getting diabetes?

You can lower your risk of getting diabetes by making changes in your lifestyle. If you are overweight, losing weight can help. Losing weight also helps lower your blood pressure and cholesterol levels.

Physical activity of any kind can help. Your exercise routine should include 30 minutes of moderate physical activity (such as walking) at least five times a week. Ask your doctor what exercise level is safe for you.

Following a healthy diet also is important. Eat foods like salads, vegetables, fruits, whole grains, fish, beans, poultry and other meats. Don't eat a lot of sugar, honey or molasses. Eat foods made with whole grains instead of white flour.

Less than 30 percent of your total daily calories should come from fat. Less than 10 percent of your daily calories should come from saturated fat. Carbohydrates should make up 50 to 60 percent of your total daily calories. Your diet also should include at least 20 grams of fiber per day.

Your doctor might refer you to a dietitian or diabetes educator to help you change your eating habits.

Can medicine help prevent or delay diabetes?

Diabetes medicines are not as effective as diet and physical activity. However, your doctor might prescribe medicine if you are at high risk for diabetes and have other medical problems, such as obesity, a high triglyceride level, a low HDL cholesterol level or high blood pressure.

More Information

For more information talk to your doctor.

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Written by familydoctor.org editorial staff.

Impaired Glucose Tolerance and Impaired Fasting Glucose by Shobha S. Rao, M.D., Phillip Disraeli, M.D., and Tamara McGregor, M.D. (American Family Physician April 15, 2004, http://www.aafp.org/afp/20040415/1961.html)

Reviewed/Updated: 05/07
Created: 01/07