The Top 10 Longevity Biomarkers You Should Be Tracking

When your GP reviews your blood test results, they're looking for values that fall outside the standard reference range — the range deemed "normal" for a general population. But "normal" doesn't mean optimal. Standard ranges are designed to detect disease, not to optimise health or predict longevity.

If you're serious about living longer and living better, you need to track specific biomarkers — and aim for ranges that are tighter than what's printed on your pathology report.

1. HbA1c (Glycated Haemoglobin)

HbA1c reflects your average blood sugar over the past 2–3 months. While a standard range of up to 5.6% is considered non-diabetic, longevity researchers recommend keeping it below 5.0%. Elevated HbA1c is associated with accelerated ageing, cardiovascular disease, and cognitive decline, even within the "normal" range.

2. Fasting Glucose

A snapshot of blood sugar regulation. Optimal fasting glucose sits between 4.0–4.7 mmol/L — significantly tighter than the standard 3.9–5.5 mmol/L. Research from the Lancet Diabetes & Endocrinologyshows that fasting glucose above 5.0 mmol/L is associated with incrementally higher cardiovascular risk.

3. High-Sensitivity C-Reactive Protein (hs-CRP)

This is your body's smoke alarm for chronic, low-grade inflammation — the kind that drives heart disease, cancer, and neurodegeneration. While < 3.0 mg/L is the standard cutoff, optimal is below 1.0 mg/L. The JUPITER trial demonstrated that reducing hs-CRP significantly lowers cardiovascular events.

4. Lipid Panel (with ApoB)

Total cholesterol alone is a blunt instrument. What matters most is the number and type of atherogenic particles — measured by ApoB. An optimal ApoB is below 0.7 g/L (longevity-focused clinicians recommend even lower for high-risk individuals). Don't ignore triglycerides, HDL-C, and LDL particle count either.

5. Vitamin D (25-Hydroxyvitamin D)

In Australia, despite our sunshine, up to one-third of adults are vitamin D deficient. The standard range starts at 50 nmol/L, but optimal levels for immune function, mood, and longevity are 100–150 nmol/L. Low vitamin D is associated with all-cause mortality in multiple large cohort studies.

6. Iron & Ferritin

Ferritin — your body's iron storage protein — is a double-edged sword. Too low, and you're fatigued with impaired immunity. Too high (above 150 μg/L), and you may be dealing with excess oxidative stress. The sweet spot is 40–150 μg/L, with optimal around 70–100 μg/L for most adults.

7. Thyroid-Stimulating Hormone (TSH)

TSH is the gatekeeper of metabolic rate, energy, and cognitive function. Standard ranges are broad (0.5–4.0 mIU/L), but many endocrinologists consider 1.0–2.5 mIU/L optimal. Subclinical thyroid dysfunction — where TSH drifts high but stays "normal" — is remarkably common and underdiagnosed.

8. Sex Hormones (Testosterone & Oestrogen)

Declining sex hormones aren't just about libido. Low testosterone in men is linked to increased cardiovascular mortality, while oestrogen imbalances in women affect bone density, cognition, and mood. Track these from your thirties to establish your personal baseline.

9. Homocysteine

An amino acid that, when elevated (> 10 μmol/L), indicates poor methylation and increased risk of cardiovascular disease, cognitive decline, and stroke. Optimal is below 8 μmol/L. B vitamins (B6, B12, folate) are key regulators.

10. Apolipoprotein B (ApoB)

ApoB deserves its own spotlight. It measures the total number of atherogenic particles in your blood — a far superior predictor of cardiovascular risk compared to LDL cholesterol alone. Leading cardiologists like Dr Peter Attia consider ApoB the single most important lipid marker for longevity.

The Takeaway

Standard reference ranges are population averages — they tell you when you're sick, not when you're thriving. By targeting optimal ranges, you're investing in prevention rather than waiting for disease to declare itself. Track these 10 biomarkers at least annually, and work with a health professional who understands the difference between normal and optimal.

References

1. Ridker PM, et al. Rosuvastatin to Prevent Vascular Events in Men and Women with Elevated C-Reactive Protein. N Engl J Med. 2008;359(21):2195-2207. doi:10.1056/NEJMoa0807646
2. Ference BA, et al. Low-density lipoproteins cause atherosclerotic cardiovascular disease. Eur Heart J. 2017;38(32):2459-2472. doi:10.1093/eurheartj/ehx144
3. Emerging Risk Factors Collaboration. Diabetes mellitus, fasting glucose, and risk of cause-specific death. N Engl J Med. 2011;364(9):829-841. doi:10.1056/NEJMoa1008862
4. Autier P, et al. Vitamin D status and ill health: a systematic review. Lancet Diabetes Endocrinol. 2014;2(1):76-89. doi:10.1016/S2213-8587(13)70165-7
5. Snyder PJ, et al. Effects of Testosterone Treatment in Older Men. N Engl J Med. 2016;374(7):611-624. doi:10.1056/NEJMoa1506119