Risk Factors for Type 1 Diabetes

An estimated 500,000 to 1 million people have type 1 diabetes. About 1 in 100 people in the general population are at risk of developing the disease before age 70. One-third will develop it before age 20. Approximately 5-10 percent of all people with diabetes in the U.S. have type 1.

Risk factors for this disease include the following:

  • A parent with type 1 diabetes
  • A sibling with type 1 diabetes
  • Being Caucasian. Caucasians are more at risk than people from other ethnic groups

Risk Factors for Type 2 Diabetes

An estimated 15 million people have type 2 diabetes. The risk of developing type 2 diabetes in the general population is 1 in 9 individuals. People with this disease represent roughly 90-95 percent of all cases of diabetes in the U.S.

Risk factors for this disease include the following:

  • Being over age 45
  • Having a family history of the disease
  • Being overweight
  • Not exercising regularly
  • Being of a certain racial or ethnic group (African American, Hispanic/Latino American, Native American or Asian American/Pacific Islander).
  • Having a low HDL (high-density lipoprotein) or high triglycerides
  • Having had gestational diabetes during pregnancy

Risk Factors for Gestational Diabetes

An estimated 2-5 percent of pregnant women will develop gestational diabetes, a condition that occurs only during pregnancy. Roughly 40 percent of these women will develop type 2 diabetes within four years of the pregnancy. The risk is lower, however, in women who are less overweight.

Risk factors for gestational diabetes include the following:

  • Overweight before the pregnancy
  • Over the age of 25
  • Family history of diabetes
  • Are African American, Hispanic/Latino American, Native American, Asian American or Pacific Islander
  • Having had a child weighing more than 9 pounds
  • Having had a stillbirth of unknown cause 

New Risk Categories for Diabetes

In 1997, the American Diabetes Association (ADA) identified two conditions that may predispose individuals to developing type 2 diabetes. They are:

  • Impaired glucose tolerance (IGT). This condition exists when blood glucose levels are between 140-199 mg/dl two hours after ingesting the sugary drink of a glucose tolerance test. A normal blood glucose reading at two hours is less than or equal to 140 mg/dl.
     
  • Impaired fasting glucose (IFG). This condition exists when fasting blood glucose levels are between 110-125 mg/dl. Fasting means that you haven’t had anything to eat or drink, except water, for eight hours. These levels are higher than normal but not high enough for a diagnosis of diabetes, which is 126 mg/dl or higher. A normal blood glucose reading is less than 110 mg/dl.