HOMA2-IR is the updated, computer-model version of HOMA that uses nonlinear equations to estimate insulin resistance from fasting glucose and fasting insulin (or C-peptide). It's considered more accurate than the original HOMA1-IR, especially at higher insulin levels, and reports an index where 1.0 reflects a reference healthy adult.
HOMA2-IR is the preferred HOMA model in modern endocrinology research because it accounts for hepatic and peripheral glucose resistance more realistically than HOMA1. Values below 1.25 reflect strong insulin sensitivity; 1.25–1.8 signals early metabolic stress; above 1.8 reflects clinically meaningful insulin resistance. Track alongside HOMA2-%B and HOMA2-%S for a complete picture of beta-cell function and sensitivity.
Optimal HOMA2-IR: 0.75-1.25 index.
Typically re-tested every 10 weeks.