Quick answer
The most useful longevity blood tests track metabolic, cardiovascular and nutritional health: HbA1c for blood sugar, ApoB and a lipid panel for heart risk, plus kidney and liver function, ferritin, vitamin B12 and, where appropriate, vitamin D and hs-CRP. Testing once a year, with the same lab and conditions, lets you spot trends early.
Key takeaways
- HbA1c reflects average blood sugar over about three months: below 5.7% is normal, 5.7–6.4% indicates prediabetes.
- ApoB counts the particles that drive atherosclerosis and can add information beyond LDL cholesterol.
- Routine vitamin D testing is not recommended for most healthy adults, but some groups benefit from supplementing.
- Trends over time matter more than a single result. Test consistently, ideally with the same lab.
- Always interpret results with a clinician, especially anything outside the reference range.
Why track blood biomarkers at all?
Many of the conditions that shorten healthspan, including type 2 diabetes, cardiovascular disease and nutrient deficiencies, develop silently for years. Blood tests can show the direction of travel long before symptoms appear, when lifestyle changes and targeted nutrition have the most leverage.
The core longevity blood panel
| Biomarker | What it tells you | Worth knowing |
|---|---|---|
| HbA1c | Average blood glucose over ~3 months | <5.7% normal; 5.7–6.4% prediabetes; ≥6.5% diabetes range 1 |
| Fasting glucose | Blood sugar at a single point | 100–125 mg/dL (5.6–6.9 mmol/L) indicates prediabetes 1 |
| ApoB | Number of atherogenic lipoprotein particles | A useful marker alongside LDL, especially when triglycerides are raised 2 |
| Lipid panel | LDL, HDL, triglycerides, non-HDL cholesterol | Consensus advice is for labs to report non-HDL cholesterol routinely 2 |
| Lipoprotein(a) | A largely inherited cardiovascular risk factor | Mostly genetically set, so one measurement is often enough. Ask your doctor. |
| hs-CRP | Low-grade inflammation | Can rise temporarily after illness or hard exercise, so interpret in context |
| Ferritin & iron studies | Iron stores | Especially relevant with heavy periods, plant-based diets or endurance training |
| Vitamin B12 | Nerve and blood health | Relevant for vegans, older adults and people taking metformin or acid-reducing medicines |
| Kidney & liver function | eGFR, creatinine, ALT and related enzymes | Baselines that matter for supplement and medication safety |
Why ApoB is getting so much attention
Standard LDL cholesterol measures how much cholesterol is carried in LDL particles. ApoB instead counts the particles themselves, since each atherogenic particle carries one ApoB molecule. Because particle number drives plaque build-up, ApoB can reveal risk that LDL cholesterol misses, particularly in people with high triglycerides, where LDL cholesterol calculations are less accurate. A joint European Atherosclerosis Society and EFLM consensus statement supports non-HDL cholesterol or ApoB as secondary targets in these patients 2.
Should you test your vitamin D?
Perhaps surprisingly, not routinely for most healthy adults. The Endocrine Society’s 2024 guideline suggests against routine vitamin D blood testing in the general population. It suggests empiric vitamin D for specific groups, including adults aged 75 and over, pregnant people and people with high-risk prediabetes 3.
Large trials also temper expectations. In the VITAL trial of 25,871 adults, 2,000 IU of vitamin D daily did not lower the incidence of invasive cancer or major cardiovascular events compared with placebo 4. Testing is still sensible when there is a clinical reason, such as bone health concerns, malabsorption or certain medicines.
How often should you get blood tests?
- Annually is a practical rhythm for most healthy adults tracking trends.
- More often (every 3–6 months) when you are actively changing something, such as a new protocol, diet or medication, and want to see its effect.
- Keep conditions consistent: same lab, same time of day, same fasting status, and avoid very hard exercise the day before.
Frequently asked questions
What is the single most important blood test for longevity?
There is no single test, but HbA1c (metabolic health) and ApoB or a full lipid panel (cardiovascular risk) cover two of the biggest drivers of lost healthy years. Discuss your full panel with a clinician.
Do I need to fast before a longevity blood panel?
HbA1c and ApoB do not require fasting, but fasting glucose and triglycerides do. Many people fast 8–12 hours so every marker can be measured in one draw. Follow your lab’s instructions.
Can supplements change my blood test results?
Yes. Biotin can interfere with some lab assays, creatine can raise creatinine, and iron or B12 supplements change their own markers. Tell your clinician and lab what you take.
What does it mean if my results are “normal” but not optimal?
Reference ranges describe a typical population, not necessarily ideal health. Values drifting in the wrong direction within the normal range can still be worth acting on with lifestyle changes. Review trends with a clinician.
Sources
- American Diabetes Association Professional Practice Committee. 2. Diagnosis and classification of diabetes: Standards of Care in Diabetes—2024. Diabetes Care. 2024;47(Suppl 1):S20–S42. doi.org/10.2337/dc24-S002
- Langlois MR, et al. Quantifying atherogenic lipoproteins: current and future challenges in the era of personalized medicine and very low concentrations of LDL cholesterol. A consensus statement from EAS and EFLM. Clin Chem. 2018;64(7):1006–1033. doi.org/10.1373/clinchem.2018.287037
- Demay MB, et al. Vitamin D for the prevention of disease: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2024;109(8):1907–1947. doi.org/10.1210/clinem/dgae290
- Manson JE, et al. Vitamin D supplements and prevention of cancer and cardiovascular disease (VITAL). N Engl J Med. 2019;380(1):33–44. doi.org/10.1056/NEJMoa1809944
Medical disclaimer: This article is for general information and education only and is not medical advice. It does not replace diagnosis or treatment by a qualified clinician. Talk to your doctor or pharmacist before starting supplements, especially if you are pregnant, take medicines or have a medical condition. Evidence reviewed as of 16 September 2026.
