Verbatim response from Claude
Blood Biomarkers That Actually Matter for Longevity
Tier 1: Strong Evidence
Metabolic Health
- Fasting insulin & HOMA-IR – arguably the most important; insulin resistance underlies most chronic disease
- HbA1c – long-term glucose control
- Fasting glucose
- Triglycerides & Triglyceride:HDL ratio – strong cardiovascular and metabolic signal
Cardiovascular
- ApoB – better than standard LDL for predicting heart disease risk
- Lp(a) – genetic risk factor most people never test
- hs-CRP – chronic inflammation marker
Tier 2: Very Useful
- Homocysteine – cardiovascular and cognitive risk
- Vitamin D (25-OH) – affects hundreds of processes
- Ferritin – iron overload is underappreciated
- TSH – thyroid function affects everything
Tier 3: Emerging/Promising
- IGF-1 – growth and aging tradeoffs
- GDF-15 – stress and aging signal
- NAD+ levels (harder to measure reliably)
Recommended Testing Services
- Function Health – 100+ biomarkers, physician reviewed
- Inside Tracker – good for athletes, personalized recommendations
- LabCorp/Quest – standard but requires doctor order
- Marek Health – popular in longevity community
Bottom line: ApoB, fasting insulin, and hs-CRP are the most overlooked by standard checkups.