Key takeaways
Diabetes affects how your body makes or uses insulin, which controls blood sugar (glucose). Untreated high blood sugar can damage blood vessels and nerves over time.
Get tested if you have symptoms like extreme thirst, frequent urination, blurry vision, constant tiredness, or cuts that won’t heal. Testing is also recommended if you’re overweight with certain risk factors, or if you’re over age 45.
Common diabetes tests include the A1C test (average blood sugar over about 3 months), fasting blood sugar, random blood sugar, and the oral glucose tolerance test. Pregnancy screening may include glucose challenge and tolerance tests to check for gestational diabetes.
Diabetes is a chronic condition that affects the body’s ability to either produce or use insulin. Insulin is a hormone which regulates sugar (glucose) in our bloodstream. Without insulin, our body can’t properly store sugar or use it for energy.
Untreated
results in high blood sugar (blood glucose), which can damage blood vessels and nerves over time.
This can cause a variety of symptoms and serious health complications, including:
difficulty seeing
tingling and numbness in the hands and feet
increased risk for a
or
Receiving a timely diabetes diagnosis and treatment can resolve uncomfortable symptoms, prevent long-term health problems, and help you get back to your life.
Diabetes is a common chronic health condition. The Centers for Disease Control and Prevention (CDC) reported in 2018 that around
of Americans had diabetes, with the majority having
.
It may be hard to detect that you have diabetes in its early stages, because symptoms can be subtle or come on slowly.
You should get tested for diabetes if you are experiencing any of the following signs or symptoms of diabetes:
extreme thirst
feeling tired all the time
feeling very hungry, even after eating
blurry vision
frequent urination
sores or cuts that won’t heal
People with certain risk factors should consider being tested for diabetes even if they aren’t experiencing symptoms.
The
American Diabetes Association (ADA)
recommends that you undergo diabetes testing if you’re overweight (body mass index greater than 25) and fall into any of the following categories:
you’re a high-risk race or ethnicity, including: Black (African American)
Latino
Native American
Pacific Islander
Asian American
you have
, high triglycerides, low HDL cholesterol, or
you have a family history of diabetes
you have a personal history of abnormal blood sugar levels or signs of
you don’t engage in regular physical activity
you’re a woman with a history of
polycystic ovary syndrome (PCOS)
or
. If you’re another gender and have a history of these health conditions, you may also be at risk, and should get tested.
The ADA also recommends you undergo initial blood sugar testing if you’re over the age of 45. This helps you establish a baseline for blood sugar levels.
Because your risk for diabetes increases with age, testing can help you identify your chances for developing it.
Blood testing allows a doctor to determine your blood sugar levels when evaluating you for diabetes. There are different kinds of diabetes blood tests.
A1c test
Blood testing allows a doctor to determine the levels of blood sugar in the body. The
is one of the most common because its results estimate blood sugar levels over time, and you don’t have to fast before the test.
The A1C test is also known as the glycated hemoglobin test. It measures
has attached itself to the hemaglobin (a protein) on your red blood cells.
A1C test measures your average blood sugar for about 3 months, which is the lifespan of red blood cells. The test requires drawing only a small amount of blood. The blood can be taken by a poke from a finger stick, or drawn from your arm.
Test resultIndicated condition5.6% or lowerNormal5.7% to 6.4%Prediabetes6.5% or greaterDiabetesSome people may have varied results using the A1C test. This includes people with kidney disease and hemoglobin variants. Your doctor may suggest alternate diabetes tests in these circumstances.
A1C testing is also used in managing diabetes. Usually the goal for someone in treatment for diabetes is 7 percent or less. However, your A1C goal will be individualized based on your health status.
Random blood sugar test
A random blood sugar test involves drawing blood at any given time, no matter when you last ate.
Results of this test equal to or greater than
per deciliter (mg/dL) indicate diabetes.
Fasting blood sugar test
Fasting blood sugar tests involve having your blood drawn after you’ve fasted overnight, which usually means not eating for 8 to 12 hours.
Test resultIndicated condition99 mg/dL or lowerNormal100 to 125 mg/dLPrediabetes126 mg/dL or greaterDiabetesOral glucose tolerance test
The oral glucose test (OGTT) takes place over the course of 2 hours.
First, your blood sugar is tested. Then, you’re given a sugary drink. After 2 hours, your blood sugar levels are tested again.
Test resultIndicated condition139 mg/dL or lowerNormal140 to 199 mg/dLPrediabetes200 mg/dL or greaterDiabetes
aren’t always used to diagnose diabetes. But doctors often use them if they think you may have
.
The body produces chemicals called
when fat tissue is used for energy instead of glucose. Labs can test urine for these ketone bodies.
Very high ketone levels can indicate type 1 diabetes. In some cases, high ketones may also be a sign of type 2 diabetes. However, ketones are also present in people who fast. So it’s not always an indicator of diabetes.
can occur when you’re pregnant, and usually goes away after giving birth. The CDC explains that gestational diabetes can
of having a large baby that needs C-section delivery, or having a baby that develops type 2 diabetes later in life.
The
suggests that pregnant women with any risk factors for diabetes be tested at their first prenatal visit. Gestational diabetes happens in the second and third trimester.
Doctors may use two types of glucose tests to diagnose gestational diabetes. These tests evaluate how your body processes sugar.
Initial glucose challenge test
The initial glucose challenge screening test is structured like this:
You drink a glucose syrup solution given by your doctor.
Your blood is drawn an hour later to measure your blood sugar level.
A result
is considered normal. A higher-than-usual reading indicates the need for further testing.
These are the steps for further glucose tolerance testing:
You must fast (not eat) overnight.
Your initial blood sugar level is measured.
You drink a cup of high-sugar solution.
Your blood sugar is then checked hourly for 3 hours.
Gestational diabetes is indicated if results show two or more higher-than-usual readings.
2-hour glucose tolerance test
This test has a similar procedure to the previous one. Your blood sugar is measured 2 hours after drinking the glucose solution.
One out-of-range value indicates gestational diabetes.
After 2 hours, a normal reading would be less than 153 mg/dL.
Diabetes is a chronic health condition, but it’s very treatable. It’s possible to manage your diabetes and live a healthy, full life. Untreated, diabetes can cause serious long-term health effects and even become life threatening.
Getting tested for diabetes in a timely manner is essential. If you have a history of the condition in your family or are experiencing symptoms (including thirst and increased urination), you should be tested. Pregnant people with any risk factors should be tested for at their first natal visit to prevent gestational diabetes.
Diabetes is evaluated through different types of blood and urine tests. The right test for you will depend on your age, symptoms, and overall health.