The 12 Longevity Biomarkers You Should Be Tracking (And What They Mean)

Why Standard Annual Blood Tests Miss the Point#

A standard annual physical typically includes: CBC, basic metabolic panel, TSH, and a lipid panel. These tests are designed to detect existing disease — not to identify risk years before disease manifests.

The longevity medicine approach is fundamentally different: identify and correct risk factors decades before they become disease. This requires a different, more specific set of markers.

Here are the 12 biomarkers that leading longevity physicians — including Peter Attia, David Sinclair, and the teams at Fountain Life, Function Health, and similar clinics — consistently highlight as most predictive of healthspan and lifespan.

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1. ApoB (Apolipoprotein B)#

What it is: ApoB is a protein present on every atherogenic (artery-clogging) lipoprotein particle — LDL, VLDL, IDL, and Lp(a). One ApoB molecule per particle means ApoB directly counts the number of atherogenic particles in your blood.

Why it matters more than LDL-C: Standard LDL cholesterol measures the mass of cholesterol inside LDL particles, not the number of particles. A person can have normal LDL-C but elevated particle count (and thus elevated cardiovascular risk) — this is called discordance and affects approximately 20% of people.

Optimal range: Under 70 mg/dL (some longevity physicians target under 60 mg/dL) Standard "normal": Under 100 mg/dL (far less aggressive) Red flag: Over 100 mg/dL warrants intervention

How to lower it: Saturated fat reduction, dietary fibre increase, statins, PCSK9 inhibitors, ezetimibe

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2. Lp(a) — Lipoprotein(a)#

What it is: A specific type of LDL particle with an additional protein (apolipoprotein a) attached. Lp(a) is highly atherogenic — it promotes both arterial plaque formation AND blood clotting — making it a dual cardiovascular risk factor.

Why it matters: Lp(a) is genetically determined and largely unaffected by diet or lifestyle. Approximately 20% of people have elevated Lp(a) (over 50 mg/dL) and most don't know it. People with very high Lp(a) (over 100 mg/dL) have dramatically elevated cardiovascular risk even with otherwise perfect lipid panels.

Test once in your lifetime (it doesn't change much): Under 30 mg/dL is optimal; over 50 mg/dL warrants aggressive risk management of all other factors; over 100 mg/dL is very high risk.

How to lower it: Very limited options currently. Niacin has modest effect. PCSK9 inhibitors reduce it 20–25%. RNA therapies (inclisiran, pelacarsen) in development may provide the first effective treatment.

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3. Fasting Insulin#

What it is: Insulin produced by the pancreas during an overnight fast. Reflects baseline insulin secretion and early insulin resistance.

Why it matters: Fasting glucose typically remains "normal" for years while insulin resistance develops — the pancreas compensates by producing more insulin. Fasting insulin catches this compensation early.

Chronically elevated insulin is associated with accelerated ageing through mTOR overactivation, increased inflammation, accelerated cell proliferation, and cardiovascular disease.

Optimal: Under 5 µIU/mL (fasting) Acceptable: 5–10 µIU/mL Concerning: Over 10 µIU/mL (insulin resistance likely even with normal glucose)

Request explicitly — most standard panels do not include fasting insulin.

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4. HbA1c (Glycated Haemoglobin)#

What it is: The percentage of haemoglobin coated with glucose — a 90-day average of blood sugar.

Longevity optimal: Under 5.3% (not just "non-diabetic" under 5.7%) Pre-diabetes range: 5.7–6.4% (already associated with increased mortality risk) Diabetic: 6.5%+

Even within the "normal" range, each 0.1% increase in HbA1c above 5.0% is associated with increasing all-cause mortality risk in large cohort studies.

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5. hs-CRP (High-Sensitivity C-Reactive Protein)#

What it is: A marker of systemic inflammation produced by the liver in response to inflammatory signals.

Why it matters: Chronic low-grade inflammation — "inflammaging" — is a central mechanism of biological ageing, accelerating cardiovascular disease, neurodegeneration, cancer, and metabolic dysfunction. hs-CRP is the most accessible measure of systemic inflammatory burden.

Optimal: Under 0.5 mg/L Acceptable: 0.5–1.0 mg/L Elevated risk: Over 1.0 mg/L High risk: Over 3.0 mg/L (cardiovascular risk equivalent to smoking)

Important: hs-CRP transiently elevates with any infection, injury, or illness. Always measure when healthy.

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6. Fasting Triglycerides#

What it is: Blood fats measured after an overnight fast — largely derived from carbohydrate and alcohol metabolism.

Longevity optimal: Under 80 mg/dL Acceptable: 80–150 mg/dL Elevated: Over 150 mg/dL Very high: Over 500 mg/dL (pancreatitis risk)

Triglycerides are one of the most lifestyle-responsive markers — responding dramatically to dietary carbohydrate and alcohol reduction within weeks. A ratio of TG:HDL over 3.0 is a strong indicator of insulin resistance and small, dense LDL particles.

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7. HDL Cholesterol#

What it is: "Good cholesterol" — HDL particles transport cholesterol from peripheral tissues back to the liver for excretion.

Optimal: Over 60 mg/dL (men); over 70 mg/dL (women) Acceptable: 40–60 mg/dL (men); 50–70 mg/dL (women) Low risk marker: Under 40 mg/dL (men); under 50 mg/dL (women)

Caveat: Very high HDL (over 90 mg/dL) is not necessarily protective and may indicate dysfunctional HDL. The U-shaped relationship means extremely high HDL is associated with increased mortality in some studies.

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8. Homocysteine#

What it is: An amino acid produced from methionine metabolism. Elevated homocysteine damages arterial walls and promotes blood clotting.

Optimal: Under 8 µmol/L Acceptable: 8–12 µmol/L Elevated: Over 15 µmol/L (independent cardiovascular risk factor)

Why it matters: Elevated homocysteine is highly treatable — folate, B6, and B12 supplementation normalises most cases. It is also associated with cognitive decline and Alzheimer's risk.

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9. 25-Hydroxyvitamin D#

What it is: The storage form of Vitamin D — the standard test for Vitamin D status.

Optimal for longevity: 50–80 ng/mL (125–200 nmol/L) Sufficient: 40–50 ng/mL Deficient: Under 30 ng/mL (affects 40%+ of adults)

Test twice yearly (spring and autumn) if supplementing to confirm dose adequacy.

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10. Testosterone (Total and Free)#

What it is: The primary anabolic hormone — affects muscle mass, bone density, mood, libido, cognitive function, and cardiovascular health in both sexes.

Men — optimal total T: 600–900 ng/dL Men — red flag: Under 400 ng/dL (hypogonadal range) Women — optimal: 30–70 ng/dL

Request free testosterone alongside total — bound testosterone is inactive; free testosterone determines actual hormonal activity. SHBG (sex hormone binding globulin) affects free T levels significantly and should be measured simultaneously.

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11. IGF-1 (Insulin-like Growth Factor 1)#

What it is: A growth hormone-dependent hormone that promotes cell growth and proliferation.

The longevity paradox: Higher IGF-1 during growth and early adulthood supports muscle and bone development. But chronically elevated IGF-1 in older adults is associated with accelerated ageing and increased cancer risk (it promotes cellular proliferation in damaged cells). Centenarians consistently show lower IGF-1 than age-matched non-centenarians.

Target for longevity: Mid-normal range for age — not the top of the range Flag for low IGF-1: Under 70 ng/mL may indicate growth hormone deficiency

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12. DHEA-S (Dehydroepiandrosterone Sulfate)#

What it is: An adrenal hormone that declines progressively with age — sometimes called the "youth hormone." It is a precursor to both testosterone and oestrogen.

Why it matters: DHEA-S is one of the most reliable markers of biological age. Its level at 40–50 predicts mortality risk in multiple cohort studies. Low DHEA-S correlates with sarcopenia, cognitive decline, and cardiovascular disease.

Optimal: Top quartile for your age group Flag: Significantly below age-expected values

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How to Get These Tests#

Standard approach: Request individual tests from your GP or primary care physician. Not all will agree to "non-standard" panels — explain you want comprehensive cardiovascular and metabolic risk assessment.

Function Health ($499/year): Tests 160+ biomarkers including all of the above, with physician interpretation.

InsideTracker: Tests 40+ markers with personalised recommendations — good interface, slightly less comprehensive than Function Health.

Marek Health: Best for testosterone and hormonal panels with physician-supervised optimisation.

LabCorp/Quest self-order: In most US states, you can order your own blood tests directly. Heart Health Advanced Panel covers most cardiovascular markers for under $200.

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Testing Frequency#

| Marker | Frequency | |--------|-----------| | ApoB, LDL-C, TG, HDL | Every 6–12 months | | Lp(a) | Once (genetically fixed) | | Fasting insulin, HbA1c | Every 6–12 months | | hs-CRP | Every 6–12 months | | Vitamin D | Twice yearly | | Testosterone, IGF-1, DHEA-S | Annually | | Homocysteine | Annually |