Diabetes Tests

Why this test may be ordered

• To monitor blood glucose levels
• If you have symptoms of diabetes: increased thirst, frequent urination, increased hunger, fatigue, blurred vision, unexplained weight loss, sores that heal slowly, numbness or tingling in feet
• If you have risk factors for type 2 diabetes: age 35 or older, prediabetes, overweight or obesity, family history of diabetes, high blood pressure or heart disease, previous gestational diabetes, exercise less than three times a week, non-alcoholic fatty liver disease, or being African American, Hispanic or Latino, American Indian, or Alaska Native
• Screening for gestational diabetes between 24 and 28 weeks of pregnancy

Preparation and collection

Fasting (not eating or drinking) for 8 hours before a blood glucose test or oral glucose tolerance test. No special preparation needed for random blood sugar, glucose challenge test, hemoglobin A1c, or glucose in urine test.

A health care professional will take a blood sample from a vein in your arm using a small needle. For a glucose in urine test, you may use an at-home test kit with a test strip held under your urine stream.

There is very little risk to having a blood test. There may be slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly. There is no risk to having a urine test.

Understanding results

Depending on the type of test you had, your results may show one of the following:

• Your glucose is at a healthy level for you: You probably are not at risk for or do not have diabetes. Limitation: Interpretation should be discussed with your healthcare provider. Next step: No further action needed based on this result alone.
• Prediabetes: Your glucose levels are higher than what is healthy for you and you may be at risk of getting diabetes. Limitation: This is not a diagnosis of diabetes. It indicates higher risk. Next step: Your condition may be managed or even reversed by taking diabetes medicines and making lifestyle changes, including eating a healthy diet, losing weight, and increasing exercise. Talk to your provider.
• Type 1 or type 2 diabetes: Your glucose levels are high enough to indicate diabetes. Limitation: For type 1 diabetes, there is no cure, but it may be controlled with regular glucose monitoring and taking insulin. For type 2 diabetes, your condition may be managed or even reversed with medicines and lifestyle changes. Next step: Talk to your provider about how to best manage the disease. For type 2 diabetes, consider eating a healthy diet, losing weight, and increasing exercise.
• Gestational diabetes: You have diabetes that developed during pregnancy. Limitation: Most of the time, gestational diabetes goes away after giving birth, but you will be at higher risk for developing type 2 diabetes in the future. Next step: You may be able to lower your glucose levels by eating a healthy diet and getting regular exercise. Talk to your provider about treatment options.

• Urine tests are not as accurate as blood tests and are not used to diagnose diabetes; a blood test is needed to confirm a diagnosis.
• If your glucose in urine levels are too high, you will probably need a blood test to confirm the diagnosis.
• Interpretation of results should be done by your healthcare provider, as reference ranges and units are not provided here.

What to do next

If you have been diagnosed with type 1 diabetes, talk to your provider about how to best manage the disease. If you have prediabetes or type 2 diabetes, your condition may be managed or even reversed with medicines and lifestyle changes. If you have gestational diabetes, talk to your provider about treatment options. If you have other questions about your diabetes diagnosis or treatment, talk to your provider.

• What type of diabetes test is right for me?
• How should I prepare for my test?
• What do my results mean for my health?
• Do I need to monitor my blood glucose at home?
• What lifestyle changes can help manage my condition?

Evidence source

U.S. National Library of Medicine: Diabetes Tests