Fasting Insulin
Learn about Fasting Insulin levels for diabetes risk and metabolic health. Track insulin sensitivity with precision monitoring.
What is Fasting Insulin?
Fasting insulin measures the amount of insulin in your blood after fasting for at least 8 hours. Insulin is the hormone that regulates blood glucose by helping cells absorb sugar from the bloodstream, and elevated fasting levels often indicate insulin resistance.
Why is it Tested?
Doctors order fasting insulin to assess insulin resistance, evaluate metabolic syndrome, and investigate causes of hypoglycemia. It provides insight into pancreatic function and helps identify prediabetes before glucose levels become abnormal.
Normal Ranges
Reference ranges for fasting insulin:
- Normal: 2.6–24.9 mIU/mL
Many experts consider optimal fasting insulin to be <10 mIU/mL, with levels >15 mIU/mL suggesting insulin resistance.
Reference ranges vary by authority. Track yours across multiple standards with automatic unit conversions in LabsVault.
What do Abnormal Results Mean?
Abnormal results are not a diagnosis. Always discuss your results with a qualified healthcare provider before making any medical decisions.
Low Fasting Insulin
Reduced levels may indicate:
- Type 1 diabetes (pancreatic failure)
- Advanced Type 2 diabetes
- Pancreatic damage or disease
- Excessive weight loss or malnutrition
High Fasting Insulin
Elevated levels suggest:
- Insulin resistance
- Prediabetes or early Type 2 diabetes
- Metabolic syndrome
- Polycystic ovary syndrome (PCOS)
- Obesity
- Insulinoma (rare)
How to Track Over Time
Fasting insulin levels can reveal developing insulin resistance years before glucose becomes abnormal. Rising trends suggest worsening metabolic health, while declining levels during lifestyle interventions indicate improved insulin sensitivity and reduced diabetes risk.
Track your Fasting Insulin results over time
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