Verbatim response from Claude
Blood Biomarkers That Actually Matter for Longevity
Tier 1: Strong Evidence
Metabolic Health
- Fasting insulin & HOMA-IR — insulin resistance is a root cause of many diseases; standard glucose alone misses early dysfunction
- HbA1c — long-term blood sugar average
- Triglycerides & HDL ratio — better cardiovascular predictor than total cholesterol
Inflammation
- hs-CRP — high-sensitivity C-reactive protein; chronic inflammation marker
- IL-6 — deeper inflammation signal
Organ Function
- eGFR/creatinine — kidney health
- ALT/AST — liver health
- TSH — thyroid function affects nearly everything
Tier 2: Increasingly Validated
- Lp(a) — genetic cardiovascular risk, often overlooked
- ApoB — better LDL particle risk marker than standard LDL
- Homocysteine — cardiovascular & cognitive risk
- Vitamin D — immune and metabolic function
Tier 3: Emerging/Promising
- IGF-1 — growth signaling, longevity tradeoffs
- DHEA-S — aging decline marker
- Ferritin — iron overload is underappreciated
Where to Get Tested
- Function Health — comprehensive panel, physician-reviewed
- InsideTracker — includes personalized recommendations
- Marek Health — good for optimization-focused testing
- Your GP — can order most Tier 1 markers
Bottom line: Fasting insulin, ApoB, hs-CRP, and HbA1c give you the most signal per dollar.