Contributed by -Healthians Team
What is an insulin test?
Your pancreas makes a hormone called insulin that helps control the blood glucose by indicating the liver, muscles and fat cells to take in glucose from the blood. It also helps glucose to get into the body’s cells that are used for energy. If the body has sufficient energy, insulin signals the liver to take up glucose and store it as glycogen. Insulin test is used to measure the insulin levels in your blood. Elevated levels of insulin can cause the blood sugar levels to fall leading to hypoglycemia and too low levels of insulin can lead to the increase of blood sugar levels in the body resulting in a condition known as hyperglycaemia.
Who should get an insulin test?
It depends on the individual and their goals to control the blood sugar levels in the blood. Insulin test is applicable for those people who are generally advised to get their blood sugar levels tested frequently, which include:
- Pregnant women with type 1 or 2 diabetes
- Women who are pregnant with gestational diabetes
- Individuals trying a new insulin type or dosage
- People who have diabetes which is hard to control
- People who take multiple medications that may raise the risk of low sugar levels
- Those who have a history of blood sugar rising after eating
- Those who have insulin resistance
Why is the insulin test needed?
The insulin test measures blood glucose levels in the blood. If a person has diabetes, it means the body is not able to make sufficient insulin to keep the blood sugar on track. This can lead to high sugar levels in the blood which can further lead to serious health problems such as eye and nerve damage.
Insulin test indicates how the body gives a response to sugar and starch after having a meal or before the meal. The insulin test is performed if you have these signs and symptoms:
- Sweating
- Hunger
- Blurred vision
- Dizziness
- Palpitations
- Fainting
If the doctor suspects the symptoms of diseases in which blood sugar level is affected, then they may order an insulin test. These diseases include:
- Type 1 or type 2 diabetes
- Polycystic ovarian syndrome
- Heart disease
- Metabolic syndrome
- Insulinoma
- Cushing’s disease
Doctors may order an insulin test either to start insulin therapy or if they suspect insulin resistance to treat diabetes.
What does insulin test results mean?
The blood sugar levels elevate after the food is digested in the stomach. In response to that, the pancreas releases insulin so that the sugar is transferred from the blood to the cells of muscles and other tissues where it can be used as fuel. Ideally, within two hours of food intake, the blood glucose levels should return to normal. If the blood glucose level remains high, there are chances that the person might have diabetes.
Normal ranges of insulin test results are as follows:
Insulin postprandial – The normal range for insulin postprandial test falls in between 5.00 uU/mL – 55.00 uU/mL.
Insulin fasting – The normal range for insulin fasting test averages between 2.6 – 24.9 mcIU/mL
Note that these ranges may slightly vary from lab to lab. Hence, test results from different labs may also vary.
How is the insulin test done?
To conduct the test, a doctor needs a blood sample of the respective person. There are two methods of blood sample collection. They are:
- Fasting insulin test: A person needs to fast for a minimum of 8 hours before the blood test as advised by the doctor otherwise, your result is affected.
- Insulin postprandial test: Insulin postprandial test is a two-hour postprandial blood sugar test that’s used to detect diabetes. The word postprandial means after a meal; therefore, postprandial glucose concentrations refer to plasma glucose concentrations after eating. The blood sample is taken after two hours of having food.
You should inform your doctor about any pre-existing medical conditions or medicines you might be on as the conditions can influence your test results.
