Blood Glucose Testing 101
May 02, 2022
Glucose is a type of sugar that acts as your body's primary energy source. A blood glucose test measures the levels of glucose in your blood. Low glucose levels can lead to various problems within your central nervous system, such as weakness, dizziness, anxiety, nervousness, lightheadedness, and headaches. Conversely, high glucose levels are associated with diabetes, vision problems, excessive hunger and thirst, rapid heartbeat, and other symptoms. Therefore, it's essential to ensure that your blood glucose levels are balanced. Blood sugar balance helps prevent long-term, serious health problems like heart disease, kidney disease, and vision loss.
What Is Glucose?
Glucose, also known as blood sugar, is essential for maintaining the health and function of many body processes. If you have normal glucose levels, your body should function normally, and nothing out of the ordinary will stand out. However, suppose your glucose levels fluctuate outside of healthy levels. In that case, however, it can cause numerous side effects and can interfere with normal body functioning.
Glucose is the simplest form of carbohydrate known as a monosaccharide, meaning it has one sugar. Other examples of monosaccharides include fructose, galactose, and ribose. Glucose is the body's preferred fuel source and is the primary energy source for the body's cells. Therefore, it is essential to provide energy for the body to function.
Glucose comes from the food we eat—such as fruit, vegetables, dairy, and grains—or the body can make it from other substances. Glucose carries to the body's cells through the bloodstream. Several hormones, including glucagon and insulin, control glucose levels in the blood.
While glucose is essential for the health and functioning of the body, it is crucial to maintain healthy glucose levels. Conversely, if glucose levels are at unhealthy levels, it can have serious side effects.
How Is Glucose Processed in The Body?
Whenever we eat something, our body begins working right away to process glucose. But, first, enzymes in the body start breaking down food with the help of the pancreas. The pancreas is a gland in the abdomen that plays a crucial role in digestion and glucose regulation.
The pancreas produces insulin, a hormone that allows your body to use sugar from carbohydrates for energy or store them for future use. For example, when we eat, our body signals the pancreas to release insulin to manage the increased glucose level.
However, in some cases, the pancreas does not function efficiently. It, therefore, does not manage blood sugar levels as it should. Poor pancreatic function is a significant cause of diabetes. This chronic health condition affects how your body turns food into energy, resulting in too much glucose in the blood. Because of this, people with diabetes rely on insulin injections to help them process and regulate glucose in the body.
Another cause of diabetes is insulin resistance, which occurs when the liver does not recognize insulin in the body, producing more glucose than necessary. The liver is also an essential organ for processing glucose in the body. It stores glucose and makes it when needed.
What Is a Glucose Test?
These tests measure the amount of sugar or glucose in the blood at a given time. One reason these tests are done is they can help to diagnose a condition called diabetes.
A doctor will use a blood glucose testing kit to collect a sample of blood.
Types of Blood Glucose Testing
There are five primary types of blood glucose testing:
- Fasting blood sugar (FBS)
- Random blood sugar (RBS)
- 2-hour postprandial blood sugar test
- hemoglobin A1c test
- oral glucose tolerance test (OGTT)
The Fasting blood sugar (FBS) test is the most common. This test measures blood glucose levels after not eating for at least 8 hours. After fasting, you drink a liquid to drink that contains glucose. Then you test your blood sugar levels to see how your body processes the glucose after fasting. This test is often the first test done to check for prediabetes and diabetes.
Random glucose testing, also known as a casual blood glucose test, measures blood glucose levels at any time of day. Whether you are in a fasted state does not matter with this test. Random glucose testing can be helpful because a healthy person's glucose levels should not vary much throughout the day. However, if blood glucose levels vary significantly, it may mean there is an issue.
A 2-hour postprandial blood sugar test is a glucose test that measures glucose levels precisely 2 hours after eating a meal. This test is typically done at home by someone that already has diabetes to gauge if they are taking the right amount of insulin with their meals.
A hemoglobin A1c test estimates one's average glucose level over the past few months.
The oral glucose tolerance test helps to diagnose diabetes that occurs during pregnancy, also known as gestational diabetes.
Can You Do Glucose Testing Without Blood?
In most cases, glucose testing requires you to draw blood. However, there is a form of glucose testing without blood that researchers at MIT have developed. This device is known as a molecular fingerprint test.
Why Should I Get a Blood Glucose Test?
Doctors order these tests if a person has symptoms of high glucose levels or low glucose levels.
Symptoms of high blood glucose levels include:
- Excessive thirst
- Frequent urination
- Fatigue
- Slow-healing wounds
- Blurred vision
Symptoms of low blood glucose levels include:
- Nervousness
- Anxiety
- Headaches
- Lightheadedness
- Confusion
- Trembling
- Sweating
- Excessive hunger
Your doctor may also order a blood glucose test for you if you have any of the risk factors of diabetes, such as:
- High blood pressure
- Heart disease
- Being obese or overweight
- Lack of exercise
- Family history of diabetes
What Happens During a Blood Glucose Test?
What happens during a blood glucose test depends on what type of test you do. Typically, your doctor will use a small needle to take a blood sample from a vein in your arm. The blood is collected into a test tube or vial and tested to determine your glucose levels. If you do a fasting blood sugar test, you will be required to fast for at least 8 hours and be given a liquid with glucose to drink before they draw your blood.
If you do random glucose testing, you will not have to fast before the test.
If you have diabetes, your doctor may recommend you get a glucose testing kit to monitor your blood sugar at home. Most glucose testing kits include a device to prick your finger known as a lancet. This device will collect a drop of blood from your finger for testing.
What Do the Results of the Glucose Test Mean?
If your glucose test results show higher than normal glucose levels, it may mean you have or are at risk of getting diabetes in the future. High glucose levels may also be a sign of hyperthyroidism (overactive thyroid), pancreatitis, or kidney disease. On the other hand, suppose your glucose test results show lower than normal glucose levels. It may be a sign of hypothyroidism (underactive thyroid), liver disease, or too much insulin or diabetes medication.
However, abnormal results don't necessarily mean you have a medical condition. In some cases, certain medications, foods, or stress can also affect your blood glucose levels. Therefore, it is essential to talk with your doctor about your test results.
Summary
Glucose, also known as blood sugar, is essential for maintaining the health and function of many body processes. If you have normal glucose levels, then your body should function normally. Nothing out of the ordinary will stand out. Suppose your glucose levels fluctuate outside of healthy levels. In that case, however, it can cause numerous side effects and can interfere with normal body functioning.
A person diagnosed with diabetes might also use a blood glucose test to manage their condition.
There are five primary types of blood glucose testing:
- Fasting blood sugar (FBS)
- Random blood sugar (RBS)
- 2-hour postprandial blood sugar test
- hemoglobin A1c test
- oral glucose tolerance test (OGTT)
The Fasting blood sugar (FBS) test is the most common. This test measures your blood glucose levels after you have not eaten for at least 8 hours. After fasting, you drink a liquid that contains glucose. Then blood sugar levels are tested to see how your body processes the glucose after fasting. This test is often the first test done to check for prediabetes and diabetes.
If your glucose test results show higher than normal glucose levels, it may mean you have or are at risk of getting diabetes.
However, abnormal results don't necessarily mean you have a medical condition. Talk with your doctor about what your test results may mean.
References
https://www.ncbi.nlm.nih.gov/books/NBK551501/
https://www.ncbi.nlm.nih.gov/books/NBK459261/
https://www.ncbi.nlm.nih.gov/books/NBK545201/
https://www.ncbi.nlm.nih.gov/books/NBK555976/
True Health Starts with Feeding the Body
