To diagnose Type 2 diabetes, your doctor may ask for some blood tests:
Glycated haemoglobin (A1C) test: This blood test indicates your average blood sugar level for the past two to three months.
Random blood sugar test: a blood sample that is taken without fasting.
Fasting blood sugar test: a blood sample that is taken after an overnight fast.
Oral glucose tolerance test: for this test, you fast overnight, and the fasting blood sugar level is measured. Then you drink a sugary liquid, and blood sugar levels are tested periodically for the next two hours.
If you receive a diagnosis of diabetes, your doctor may also run blood tests to check for autoantibodies that are common in Type 1 diabetes. These tests help your doctor distinguish between Type 1 and Type 2 diabetes. The presence of ketones, which are the by-products from the breakdown of fat, when found in your urine also suggests Type 1 diabetes, rather than Type 2.
If you are age 45 years or older and you are overweight, it is recommended by the American Diabetes Association that you begin screening for type 2 diabetes. If the results are normal, the test should be repeated every three years.
Screening is also recommended for people who are under 45 years, are overweight and if there are other heart disease or diabetes risk factors present, such as an inactive lifestyle, a family history of type 2 diabetes, a personal history of gestational diabetes or moderately blood pressure.