HOMA-IR

HOMA-IR (Homeostatic Model Assessment of Insulin Resistance) estimates fasting insulin sensitivity from two numbers you can pull from any standard lab: fasting glucose and fasting insulin. The formula, glucose in mg/dL multiplied by insulin in µIU/mL, divided by 405, gives a single ratio that catches insulin resistance years before fasting glucose or hemoglobin A1c drift above the diabetic threshold.

Optimal range

Range varies by individual.

Test frequency

Annually as part of a metabolic panel; every three months during active weight loss, training-driven body-composition change, or any insulin-sensitizing medication trial.

When to measure

Measure as part of any metabolic baseline panel from age 30 onward, especially if there is family history of type 2 diabetes, central adiposity, fatty liver on imaging, or hypertension. Re-measure after major changes in body weight, training volume, eating window, or carbohydrate intake. Always draw fasting, 10 to 14 hours, water only, because non-fasting insulin values are essentially uninterpretable.

How to measure

Standard fasting venous blood draw for glucose and insulin; the lab will report each value, and you compute HOMA-IR yourself (glucose mg/dL × insulin µIU/mL / 405) or use any online calculator. Cost is typically $30–$60 retail when both are ordered together. Most annual physicals include glucose by default but require explicit request for fasting insulin, ask for it.

Why this biomarker matters

Insulin resistance is the earliest detectable rung on the ladder that ends in type 2 diabetes, fatty liver disease, and accelerated cardiovascular disease. By the time hemoglobin A1c crosses into pre-diabetic territory (5.7 percent), insulin output has often been compensating for a decade or more. HOMA-IR catches that compensation: a fasting insulin of 12 µIU/mL with a glucose of 95 looks reassuring on either marker alone but yields a HOMA-IR of 2.8, clearly above the insulin-resistant threshold. Reference values are well established. HOMA-IR under 1.0 indicates excellent insulin sensitivity, typical of trained, lean, healthy young adults. Values between 1.0 and 1.9 are unremarkable. From 2.0 to 2.5 suggests early insulin resistance; above 2.5 is consistent with metabolic syndrome; above 4.0 typically accompanies overt type 2 diabetes. The marker responds quickly to weight loss, structured exercise (especially zone-2 and resistance training), and time-restricted eating, meaningful HOMA-IR drops are routinely seen within eight to twelve weeks.

The prime report

Weekly performance intelligence.

New studies, protocols, and optimization frameworks delivered every Monday. No fluff, no motivation quotes — only what moves the needle.