Insulin Fasting
Understanding Insulin Fasting
What is Insulin Fasting?
An Insulin Fasting test measures the level of insulin in your blood after a fasting period of 8-12 hours. It is done when symptoms like increased thirst or urination, appetite changes, weakness, weight changes, tingling or numbness in the hands or legs, etc. are experienced by an individual.
Insulin hormone is produced and stored in the beta cells of the pancreas. It helps the body cells to uptake glucose (blood sugar) from the blood for the production of energy. Without insulin, glucose cannot reach most of the body cells and remains in the blood instead. This causes your blood glucose levels to reach dangerously high levels and may eventually lead to a life-threatening condition called diabetic coma. Therefore, it is vital for survival to maintain your insulin levels.
An Insulin Fasting test is usually advised following a low blood glucose test result and/or when someone has symptoms of low blood glucose (hypoglycemia), such as profuse sweating, nervousness or anxiety, irritability, confusion, dizziness, hunger, fast heartbeat, etc. This test is also used to detect the presence of an insulin-producing tumor in the islet cells of the pancreas (insulinoma).
Overnight fasting (8-12 hours) is recommended before undergoing an Insulin Fasting test. Do not eat or drink anything other than water during the fasting period. It is also important to inform your doctor about any medicines that you take, as some of them may affect your blood glucose levels and need to be adjusted or temporarily discontinued before the test.
Test result ranges are approximate and may differ slightly between labs depending on the methodology and laboratory guidelines. Talk to your doctor about your specific test results. The results will help them determine your medical condition, make recommendations for lifestyle modifications such as diet and exercise, decide whether or not medication will be required to manage your condition, and formulate your overall treatment plan.
What is Insulin Fasting used for?
An Insulin Fasting test can be done:
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To determine the cause of low blood sugar (hypoglycemia).
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To determine the proper production of insulin by the pancreas.
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To monitor the condition of people with type 2 diabetes.
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To determine if insulin resistance in cells is the cause of hyperglycemia (high blood sugar).
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To determine if insulin supplementation is necessary.
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To determine the presence of insulin-producing tumors (insulinomas) in the beta cells of the pancreas.
What does Insulin Fasting measure?
An Insulin Fasting test evaluates the amount of insulin available in your blood following a fasting period of about 8-12 hours, which helps in regulating glucose levels.
Glucose is a source of energy for the body to perform daily activities. Your body gets glucose from carbohydrates that are consumed in the diet. These carbohydrates are digested and converted into simple sugar (glucose). The required amount of glucose is then absorbed by the cells for the production of energy, and the remaining amount is stored in other forms like fats. Insulin hormone helps the cells to uptake glucose from the blood for utilization and storage. Thus, it is necessary to maintain insulin levels in your body.
Interpreting Insulin Fasting results
Interpretations
Normal range (Approx.): 2.0 - 25.0 uU/ml
Fasting Insulin Test is usually ordered with Fasting glucose test and the results interpreted as follows:
Fasting insulin level |
Fasting glucose level |
Disorder |
Normal |
Normal |
None |
High |
Normal or slightly high |
Insulin Resistance |
Low |
High |
Insufficient insulin production, e.g., diabetes |
Normal or high |
Low |
Hypoglycemia due to over secretion of insulin |