Insulin, Fasting
Understanding Insulin, Fasting
What is Insulin, Fasting?
An Insulin, Fasting test measures the insulin level in the blood after an overnight fast (8-12 hours). Insulin is a hormone the pancreas produces that regulates blood sugar (glucose) levels. Fasting insulin levels provide insights into insulin sensitivity (how well the body responds to insulin) and help assess glucose metabolism and the risk of developing insulin resistance-related conditions.
Insulin helps the body cells to uptake glucose (blood sugar) from the blood to produce energy. Insulin resistance occurs when cells do not respond effectively to insulin, leading to elevated blood sugar levels. An Insulin, Fasting test provides information about insulin resistance and abnormal glucose metabolism, which is commonly associated with conditions like diabetes, obesity, metabolic syndrome (a collection of conditions including abdominal obesity, high blood pressure, high blood sugar, and abnormal lipid levels), and polycystic ovary syndrome (PCOS).
An Insulin, Fasting test is usually done with other glucose-related tests, such as fasting blood glucose or oral glucose tolerance tests. Your doctor may advise this test following a low blood glucose test result and/or if you have low blood glucose (hypoglycemia) symptoms, such as profuse sweating, nervousness or anxiety, irritability, confusion, dizziness, hunger, fast heartbeat, etc. This test may also help detect the presence of an insulin-producing tumor in the islet cells of the pancreas (insulinoma).
An Insulin, Fasting test is generally safe and well-tolerated. However, as with any blood test, minimal discomfort or bruising may occur at the site where the blood sample is drawn. 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 essential to inform your doctor about any medicines you take, as some 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:
- To assess insulin levels and the body's ability to regulate blood sugar levels
- To assess diabetes risk and guide preventive measures.
- To identify insulin sensitivity and resistance that is associated with conditions like diabetes, obesity, metabolic syndrome, and polycystic ovary syndrome (PCOS).
- To guide management strategies in individuals with metabolic syndrome and PCOS.
- 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 body's ability to regulate blood sugar levels by measuring the amount of insulin in the blood after an overnight fast. 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 cells then absorb the required amount of glucose to produce 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
A fasting Insulin test is usually ordered with a Fasting glucose test, and the results are 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 |