The Insulin (Fasting) test measures the amount of insulin present in the blood after an overnight fast. Insulin is a key hormone responsible for regulating blood glucose levels by helping cells absorb sugar for energy.

This test is particularly useful for identifying insulin resistance, a condition in which the body does not respond effectively to insulin and which often precedes prediabetes, type 2 diabetes, and metabolic syndrome. It also helps in evaluating unexplained weight gain, difficulty controlling blood sugar, and hormonal or metabolic imbalances.

Clinical Importance:

• Detects early insulin resistance
• Supports assessment of prediabetes and diabetes risk
• Helps evaluate metabolic and endocrine health
• Aids doctors in planning lifestyle or treatment interventions

Patient Preparation:

• Overnight fasting is mandatory (minimum 8–12 hours)
• Only water is allowed during the fasting period

When interpreted alongside fasting blood glucose and lipid parameters, the Insulin (Fasting) test provides a comprehensive understanding of glucose metabolism and long-term metabolic health.