The specific cause of type 2 diabetes is not yet known. While research scientists do not know the cause of type 2 diabetes, they have identified risk factors that increase a person's chance of developing the disease. These risk factors for type 2 diabetes include high blood pressure, abnormal lipid levels, lack of activity, family history, and ethnicity.

• Age. People over 45 years of age are at a higher risk for diabetes.
   
• Abnormal lipid levels. Men with an HDL cholesterol ("good cholesterol") of less than 40 mg/dL and women with an HDL cholesterol of less than 50 mg/dL are at increased risk for diabetes. People with triglyceride levels of 250 mg/dL or more are also at an increased risk for the disease.
   
• Overweight. People who are overweight, which is defined as having a body mass index (BMI) greater than or equal to 25 (23 if Asian American; 26 if a Pacific Islander) are at higher risk of developing type 2 diabetes (see BMI Calculator).
   
• Family history. Statistics indicate that people with a parent or sibling with type 2 diabetes are at a higher-than-normal risk of getting the disease.
   
• Ethnicity. People of African American, American Indian, Asian American, Hispanic/Latino, or Pacific Island heritage have an increased risk of developing diabetes.
   
• Inactive lifestyle. People who exercise less than three times per week may be at an increased risk for type 2 diabetes.
   
• Blood pressure. People with blood pressure higher than 140/90 mm/Hg are at increased risk for diabetes (see High Blood Pressure).
   
• History of gestational diabetes. Women who have previously had gestational diabetes or given birth to at least one baby weighing 9 pounds or more are at increased risk for developing type 2 diabetes.