Verbatim response from Perplexity
The blood biomarkers that actually matter for longevity are those that predict cardiovascular risk, metabolic health, and systemic inflammation, with the most critical being ApoB, HbA1c, fasting insulin, and hs-CRP.
While standard health checks often focus on LDL cholesterol and total glucose, longevity experts prioritize more precise markers that detect disease risk decades earlier.
1. Top Priority: Cardiovascular Risk
The most accurate predictor of cardiovascular disease (the leading cause of death) is Apolipoprotein B (ApoB), not LDL cholesterol.
- ApoB: Measures the total number of atherogenic (disease-causing) particles in the blood. It is proven to be more accurate than LDL for predicting heart disease risk in longevity medicine [1][3][4].
- Lipoprotein(a) or Lp(a): An independent genetic risk factor for heart disease that should be tested if ApoB is elevated or if there is a family history of heart issues [1][3].
- ApoB:ApoA1 Ratio: A measure of heart disease risk that compares "bad" particle carriers to "good" ones [1].
2. Top Priority: Metabolic Health & Insulin Resistance
Blood sugar control is essential for preventing diabetes and metabolic aging, but fasting insulin detects problems long before standard tests.
- Fasting Insulin: Identifies insulin resistance 10–15 years before HbA1c levels rise, allowing for early intervention [3][16].
- HbA1c (Hemoglobin A1c): Reflects average blood sugar over the past 2–3 months. Lower levels are strongly linked to reduced diabetes risk and longer lifespan [1][2][7].
- TG:Glucose Index (Triglyceride-Glucose): A composite marker that predicts metabolic dysfunction more accurately than glucose alone [6].
3. Top Priority: Systemic Inflammation
Chronic, low-grade inflammation is a primary driver of almost all age-related diseases, including cancer and dementia.
- hs-CRP (High-sensitivity C-reactive protein): The most reliable marker for chronic inflammation. Elevated levels independently predict cardiovascular events, cancer, and accelerated aging [1][3][6].
- Fibrinogen or ESR: Secondary inflammatory markers sometimes used if hs-CRP is unclear [6].
4. Essential Supporting Biomarkers
These markers provide critical context for organ function, nutrient status, and specific disease risks:
- Homocysteine: Elevated levels indicate poor methylation and are linked to higher dementia and cardiovascular risk [3][16].
- Vitamin D: Deficiency impairs cellular function and accelerates molecular aging; optimal levels are crucial for immune and bone health [3][6].
- Kidney Function (Creatinine & eGFR): Lower creatinine levels and higher eGFR in older age are associated with longer life [5][7].
- Liver Enzymes (ALT, GGT): High levels indicate liver stress and inflammation, which shorten lifespan [7].
- Ferritin (Iron): While too much iron is harmful, centenarians in some studies showed higher iron levels than non-centenarians, suggesting a complex relationship where moderate iron storage supports longevity [5][7].
- Hormones (Testosterone, TSH, Free T3): Sex hormones and thyroid function significantly influence metabolism, energy, and the aging process [3][14][15].
Biomarkers with Surprising or Nuanced Findings
Recent research on people who reached 100 years old (centenarians) has identified some counter-intuitive associations:
- Total Cholesterol & Iron: Higher levels of total cholesterol and iron were associated with reaching 100 years, though this may reflect survival bias in older age rather than a recommendation to increase them [5][7].
- HDL Cholesterol: Slightly higher HDL ("good" cholesterol) is linked to greater longevity in centurions [7].
- Glucose: Lower glucose levels remained a consistent marker for longevity, even in older age [5][7].
Recommended Testing Frequency
For serious longevity tracking, experts recommend testing ApoB, fasting insulin, HbA1c, hs-CRP, homocysteine, and Vitamin D annually, alongside a full lipid panel and organ function tests [3].
Summary of Actionable Tests: If you are ordering a blood panel specifically for longevity, ensure it includes ApoB (replacing LDL), Fasting Insulin, HbA1c, and hs-CRP. These four markers provide the earliest and most accurate warning of future health decline [3][16].