What Is Diabetes?
Diabetes is a condition that affects the body’s
ability to either produce or use insulin. Insulin helps the body utilize blood
sugar for energy. Diabetes results in blood sugar levels (blood glucose) to
rise to abnormally high levels. Diabetes
results in damage to blood vessels and nerves, causing difficulty seeing,
tingling and numbness in the hands and feet, and increased risk for
experiencing a heart attack of stroke.
Diagnosing diabetes as quickly as possible means
patients can start treating diabetes and taking steps to live a healthier
Who Should Undergo Diabetes Testing?
In its early stages, diabetes may not cause many
symptoms. However, some people experience symptoms that include:
- sudden weight loss
- extreme thirst
- feeling tired all the time
- feeling very hungry, even after eating
- difficulty seeing
- urinating more often than usual
Other people should be tested for
diabetes, even if they are not experiencing symptoms. The American Diabetes
Association (ADA) recommends the following people undergo diabetes testing:
- anyone with a body mass index greater than 25
- patients with high blood pressure, high
cholesterol, or heart disease
- people who have a family history of diabetes
- those who do not engage in regular physical
- women with a history of polycystic ovary
The ADA also
recommends anyone who is older than age 45 undergo an initial blood sugar test.
This helps a person establish a baseline for blood sugar levels. Because a
person’s risk for getting diabetes increases with age, testing can help people
identify their risks.
Blood Testing for Diabetes
Blood testing allows a doctor to
determine the levels of blood sugar in the body. The A1C test is one of the
most common tests because its results measure blood sugar levels over time. Also
known as the glycated hemoglobin test, the test measures how much glucose has
attached itself to red blood cells in the body over the last three months.
Red blood cells have a lifespan
of about three months. Because the A1C test examines blood glucose, it measures
a person’s average blood sugar for roughly three months. The test requires
gathering only a small amount of blood. The results are measured in a
- less than 5.7 percent: normal reading
- between 5.7 and 6.4 percent: prediabetes
- greater than 6.5 percent: diabetes
While doctors can perform these
tests in-office to receive immediate results, these aren’t considered to be as
accurate as tests sent to a laboratory. Lab tests are standardized. This means
that no matter the lab performing the test, the methods to test the blood are
the same. According to the National Diabetes
Information Clearinghouse, only tests from a laboratory should be
considered definitive enough to diagnose diabetes.
Some people may have varied
results using the A1C test. This includes pregnant women or people with a
special hemoglobin variant that makes the test results inaccurate. A doctor may
suggest alternate diabetes tests in these circumstances.
Random Blood Sugar Test
A random blood sugar test
involves drawing blood at any given time, no matter when you last ate. If the
result is higher than 200 milligrams per deciliter (mg/dL) this could indicate
Fasting Blood Sugar Test
Fasting blood sugar tests involve
drawing blood after a person has not eaten overnight. Results less than 100
mg/dL are normal. Results between 100 to 125 mg/dL are considered prediabetes.
Results greater than 126 mg/dL after two tests are considered diagnostic for
Oral Glucose Tolerance Test
The oral glucose test (OGTT) is a
test that takes place over the course of two hours. A person’s blood sugar is
tested initially and then given a sugary drink. After two hours, blood sugar
levels are tested again. The results are:
- less than 140 mg/dL: normal
- between 140 and 199 mg/dL: prediabetes
- greater than 200 mg/dL: diabetes
Urine Testing for Diabetes
tests aren’t used to definitively diagnose diabetes. However, they are often
used when doctor thinks the patient may have type 1 diabetes. Laboratories can
test urine for ketone bodies. The body produces ketone bodies when fat tissue
is used for energy instead of blood sugar. If ketone bodies are in the urine,
this could indicate the person isn’t making enough insulin.
Gestational Diabetes Tests
Gestational diabetes can occur
when a woman is pregnant. Women are tested early in a pregnancy if they have a
family history of gestational diabetes or have had it before. Women who don’t
have these risk factors are tested in the second trimester instead.
Doctors may use two different
test types to diagnose gestational diabetes. The first is an initial glucose
challenge test. This test involves drinking a glucose syrup solution. Blood is
drawn after an hour to measure blood sugar levels. A result of 140 mg/dL or
less is considered normal. A higher-than-usual reading indicates the need for
The follow-up glucose tolerance
testing involves not eating anything overnight. An initial blood sugar level is
measured. The expectant mom will then drink a high-sugar solution. The blood
sugar is then checked hourly for three hours. If a woman has two or more
higher-than-usual readings, the results indicate gestational diabetes.