Understanding Your Blood Tests: Diabetes
Type 2 diabetes is a major health crisis in this country. It affects more than 30 million Americans—that’s almost 10% of the country—and it’s the 7th leading cause of death.
Even worse, things aren’t getting better—they’re getting worse. The prevalence of diabetes is expected to increase by 54 percent to more than 46 million Americans between 2015 and 2030. Annual deaths attributed to diabetes will climb by 38 percent to 385,800. And by 2030, medical and societal costs related to diabetes will top $600 billion.
This is why, when you go for your annual exam, your doctor most likely runs tests to check if you have diabetes. Knowing where you stand is extremely important, allowing you to make necessary diet and lifestyle changes to get better control of your blood sugar. To understand what all of these tests mean, though, it’s important to know how blood sugar affects you and your health.
What Is Type 2 Diabetes?
Diabetes is a disease that occurs when your blood sugar (or glucose) is too high. Glucose is your body’s main source of energy, and it comes from the food you eat.
Insulin, a hormone made by the pancreas, escorts glucose into your cells so that it can be used for energy. But when you have type 2 diabetes, your body doesn’t make enough insulin or it doesn’t use insulin properly—a condition called insulin resistance. Over time, glucose remains in your blood instead of entering your cells, which leads to consistently high blood sugar—and eventually, diabetes.
When glucose builds up in your blood, it can cause several problems. An immediate effect is that your cells become starved for energy. Over the long term, though, serious issues can develop as a result of chronically high blood sugar, including eye, kidney, nerve, and heart problems.
Early detection is crucial to not only gain control over your blood sugar, but also prevent major complications. This is why testing is so important. Here are the most common tests for diabetes, and how to decipher your results…
The hemoglobin A1C test (sometimes called “glycated hemoglobin test”) is one of the most common diabetes assessments. It requires a small blood sample, usually drawn from the arm, and you don’t need to fast for it. The A1C test gives your doctor an estimate of your blood sugar levels for about a three-month period of time.
Hemoglobin is a protein found inside red blood cells. When glucose enters your red blood cells, it attaches (or glycates) to molecules of hemoglobin. The more glucose in your blood, the more hemoglobin gets glycated.
Because red blood cells have a lifespan of about three months, the A1C test measures how much glucose has attached itself to the hemoglobin in your red blood cells over that period of time.
Results less than 5.7% are considered normal.
If results show that your A1C is between 5.7-6.4%, you have prediabetes, meaning your blood sugar levels are elevated, but not high enough to get a full diagnosis of diabetes. (If this is your result, now is the time to change your lifestyle and diet to bring your glucose down to normal range! It can be done naturally and without drugs, but you must get started immediately.)
Results equal to or greater than 6.5% indicate diabetes.
The A1C test is by far the most accurate and trusted test for diabetes. But some people may have inconsistent results or have a hemoglobin variant that makes this test inaccurate. If that’s the case, your doctor will probably order one or more of the following tests.
Fasting Plasma Glucose (or Blood Sugar) Test
This test measures your blood sugar level at a single point in time. For the most reliable results, you’re required to fast for at least eight hours—so it’s best to stop eating at night and have your blood drawn first thing in the morning.
For this test, results of less than 100 mg/dL are considered normal.
If results range from 100-125 mg/dL, it could indicate prediabetes, and results greater than 126 mg/dL mean diabetes. (Doctors will often order two tests to confirm.)
Random Blood Sugar Test
This test is similar to the fasting blood sugar test, but rather than avoiding food for a period of time before your blood draw, you can get it done at any time, no matter when you last ate.
With this test, results equal to or greater than 200 mg/dL signal diabetes.
Oral Glucose Tolerance Test
This test takes about two hours. You get an initial blood test, then you’re given a sugary drink and retested two hours later to see how your body has processed and responded to the sugar.
Results less than 140 mg/dL are normal, between 140-199 mg/dL signal prediabetes, and equal to or greater than 200 mg/dL indicate diabetes.
Other Important Diabetes Tests
Sometimes, people have no idea that they have elevated blood sugar or diabetes until a diabetic complication strikes, sending them to the doctor or hospital. For this reason, along with your annual blood work, you should also considering the following exams:
- Eye exam with dilation. High blood sugar damages blood vessels throughout the body, including the tiny vessels in your eyes—leading to diabetic retinopathy. But the damage from this condition can be prevented if it gets caught early. With the help of eye drops to enlarge the pupils, an eye doctor can look inside the eye to check for signs of leaking blood vessels.
- Podiatry exam. Diabetes can slow circulation to your extremities, causing you to lose feeling (neuropathy). A podiatrist can check for cracks, redness, sores, and other abnormalities, and also conduct what’s called a “monofilament test,” where they press a piece of nylon to different parts of your feet to see if you have any nerve damage.
Diabetes is a not a disease to be taken lightly. Understanding the different types of glucose tests, and knowing how to read your results, can put you in the driver seat toward better blood sugar control and overall health. Don’t wait…schedule your annual exams with your general practitioner, eye doctor, and podiatrist today!
Last Updated: October 11, 2018