What is HOMA-IR? Understanding Insulin Resistance Testing

HOMA-IR (Homeostatic Model Assessment of Insulin Resistance) is a calculation that uses your fasting insulin and fasting glucose levels to estimate how resistant your cells are to the effects of insulin.

Unlike a standard glucose test that only tells you if your blood sugar is "normal," HOMA-IR reveals how hard your pancreas is working to maintain that normal level.

Here's the issue with relying solely on fasting glucose: your body is remarkably good at compensating. In the early stages of insulin resistance, your pancreas simply produces more insulin to keep blood sugar in the "normal" range.

This means you could have perfectly normal glucose levels while your pancreas is working overtime—a situation that can persist for years before glucose finally rises into the pre-diabetic range.

The formula is straightforward:

HOMA-IR = (Fasting Insulin × Fasting Glucose) / 405

(When glucose is measured in mg/dL and insulin in μU/mL)

Interpreting Your Score

• Below 1.0: Optimal insulin sensitivity
• 1.0 - 1.9: Normal range
• 2.0 - 2.9: Early insulin resistance
• 3.0 and above: Significant insulin resistance

Insulin resistance doesn't just affect diabetes risk. It impacts:

• Cellular energy production — Your cells struggle to efficiently use glucose for fuel
• Inflammation — Insulin resistance promotes systemic inflammation
• Tissue repair — Impaired nutrient delivery slows recovery from injury
• Brain function — The brain is highly sensitive to metabolic dysfunction

Standard GP panels rarely include fasting insulin. At Metabolic Physio, we include both fasting insulin and glucose in our Metabolic Audit, allowing us to calculate your HOMA-IR score and identify metabolic dysfunction early—when it's most responsive to intervention.

If you're experiencing unexplained fatigue, slow injury recovery, or simply want to understand your metabolic health, consider booking a Metabolic Audit.