A simple score from your fasting glucose and insulin that estimates how insulin-resistant you are.
A calculated index (fasting glucose × fasting insulin ÷ 22.5) used as a proxy for insulin resistance.
It bundles glucose and insulin into one steady-state number. Lower means your cells respond well to insulin; higher points toward the insulin resistance that underlies type-2 diabetes and metabolic disease.
< 1.3
It’s a proxy, not a gold-standard test, and inherits the lab-to-lab variation of the insulin assay. Clinical insulin-resistance thresholds sit around 2.5; the longevity-optimal target is well below that.
Same target for men and women.
Use it as one input in a metabolic picture, interpreted with a clinician rather than in isolation.