Homeostatic Model Assessment of Insulin Resistance
HOMA-IR (Homeostatic Model Assessment of Insulin Resistance) is a mathematical formula that uses fasting glucose and fasting insulin to estimate how resistant your body's cells are to the effects of insulin. It was developed as a practical, cost-effective way to quantify insulin resistance without needing a complex insulin clamp study.
A HOMA-IR score below 1.0 is generally considered insulin sensitive; scores above 2.0–2.5 suggest significant insulin resistance; scores above 3.0 indicate marked resistance. HOMA-IR provides earlier detection of metabolic dysfunction than glucose or HbA1c alone — elevated HOMA-IR in the presence of normal fasting glucose is a red flag for metabolic disease risk that would otherwise go undetected.
FAQs
How is HOMA-IR calculated?
HOMA-IR = (fasting glucose in mmol/L x fasting insulin in mU/L) divided by 22.5. Both measurements must be from a fasting blood sample collected at the same time after 8-12 hours without food.
What HOMA-IR score is normal?
A HOMA-IR below 1.0 is considered insulin sensitive. Scores of 1.0-2.5 suggest developing resistance; above 2.5 indicates significant resistance; above 3.0 indicates marked insulin resistance. These thresholds may vary slightly between laboratories and populations.
Can I have a normal fasting glucose but high HOMA-IR?
Yes. This is the key clinical value of HOMA-IR. Fasting insulin rises to compensate for insulin resistance before fasting glucose becomes abnormal. HOMA-IR can be significantly elevated for years before fasting glucose leaves the normal range.
Is HOMA-IR included in standard blood tests?
HOMA-IR is not routinely reported but is calculated from fasting glucose and fasting insulin, both of which can be ordered. Some specialist metabolic and preventive health panels include HOMA-IR calculation automatically.
