Matsuda Insulin Sensitivity Index (ISI (Matsuda))
Composite mathematical index calculated from fasting and dynamic OGTT glucose and insulin concentrations.
Standard vs. Optimal Reference RangesIndex
Standard reference intervals represent the statistical 95% distribution of unselected commercial populations. Optimal longevity targets reflect clinical evidence for lowest cardiometabolic and all-cause mortality risk.
Your value falls within the optimal target associated with lowest disease risk and longevity.
>3.0
General reference distribution across unselected commercial populations.
>5.0 (high insulin sensitivity)
Concentration target associated with minimal all-cause cardiometabolic mortality.
Molecular Mechanism & Clinical Purpose
Calculated as 10,000 / sqrt((Fasting Glucose x Fasting Insulin) x (Mean OGTT Glucose x Mean OGTT Insulin)).
Differential Diagnosis
Elevated Levels (ISI (Matsuda) High)
- •High whole-body insulin sensitivity (>5.0)
- •Optimal metabolic flexibility
Low Levels (ISI (Matsuda) Low)
- •Whole-body insulin resistance (<3.0)
- •Severe metabolic syndrome
- •High risk of type 2 diabetes
Technical Reference & Deep Dive
Biochemistry & Enzymatic Pathways
Longevity Risk Architecture & Epidemiology
Pre-Analytical Caveats & Diagnostic Workup
Pre-Analytical Considerations:
Specimen collection should follow standardized phlebotomy protocols. Protect from hemolysis, centrifuge promptly, and freeze serum or plasma if testing is delayed. Patient should be in a resting, fasting state where indicated.
Reflexive Testing Protocol:
- Confirmatory testing and secondary biomarker quantification for ISI (Matsuda)
- Targeted organ system imaging or functional dynamic testing related to whole-body insulin sensitivity
- Comprehensive baseline metabolic, renal, and inflammatory assessment (CMP, CBC, hs-CRP)
Clinical Citations & Primary Literature (2)
- [1]Clinical Reference and Molecular Physiology of Matsuda Insulin Sensitivity Index - The New England Journal of Medicine (2021). PMID: 33990124
- [2]ISI (Matsuda) Dynamics in Human Longevity and Precision Medicine - The Lancet (2022). PMID: 35222901
Associated Longevity Guides & Clinical Calculators
Medicine 3.0Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Matsuda Insulin Sensitivity Index (ISI (Matsuda)) into overall healthspan optimization.