You have a higher risk for diabetes if you have any of the following:
Persons from certian ethnic groups, including African Americans, Hispanic Americans, and Native Americans, all have high rates of diabetes
Everyone over 45 should have their blood glucose checked at least every 3 years. Regular testing of random blood glucose should begin at a younger age, and be performed more often if you are at higher risk for diabetes.
See: Diabetes
American Diabetes Association. Screening for type 2 diabetes. Diabetes Care. 2004; 27(Suppl.1):S11-S14.