Normal Fasting Insulin — Am I Normal?
Fasting insulin from a morning blood draw (8+ hours fasted). Rises years before glucose does.
What is a normal fasting insulin level?+
Most labs flag "normal" up to ~25 µIU/mL, but that range is far too loose for metabolic health. Optimal fasting insulin is under about 5–6 µIU/mL; rising values in the high single digits and teens signal early, reversible insulin resistance long before fasting glucose or HbA1c move.
Why measure fasting insulin instead of glucose?+
The pancreas raises insulin output to hold glucose steady as cells become resistant. So insulin climbs first — fasting glucose and HbA1c stay "normal" until compensation finally fails. Insulin is the earliest, most actionable warning.
How is fasting insulin related to HOMA-IR?+
HOMA-IR combines fasting insulin and fasting glucose into one insulin-resistance index: (glucose × insulin) / 405 in mg/dL. Use the HOMA-IR calculator to turn this number plus your glucose into a single score.
How do I lower fasting insulin?+
Build muscle (the main glucose sink) with resistance training, cut refined carbohydrate and sugary drinks, raise fiber and protein, walk after meals, and fix sleep. These reliably improve insulin sensitivity within weeks.
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