Common longevity terms

The protein coating every "bad" cholesterol particle. It counts the actual number of particles, not just how much cholesterol they're carrying.

Every LDL, VLDL and Lp(a) particle in the blood carries exactly one ApoB molecule on its surface, so measuring ApoB directly counts the number of potentially artery-clogging particles circulating, whatever how much cholesterol each one happens to be carrying. Many researchers and clinicians consider this a more accurate cardiovascular risk marker than standard LDL cholesterol alone, since two people with identical LDL cholesterol can have very different particle counts.

Where to compareOn the comparison page, 4 of the 9 blood tests and programs that list their markers include ApoB as standard (Everlab, Hemexa, i-screen and Listen Health), and 2 sell it as an add-on (Bloody Good and MediTests). Each profile shows the full marker grid. Checked 3 Nov 2026.

A cholesterol-carrying particle whose level is set almost entirely by genetics, not diet or lifestyle.

Lp(a) is an independent cardiovascular risk factor that's largely inherited rather than influenced by what you eat or how you exercise. Because it's genetically fixed, it typically only needs to be checked once in a lifetime rather than tracked repeatedly like a lipid panel. It's tested alongside, not instead of, standard cholesterol markers, since it captures a different, largely non-modifiable piece of risk.

Where to compareOn the comparison page, 4 of the 9 blood tests and programs that list their markers include Lp(a) as standard (Everlab, Hemexa, i-screen and Listen Health), and 2 sell it as an add-on (Bloody Good and MediTests). Checked 3 Nov 2026.

A marker of low-grade inflammation in the body, measured with a far more sensitive test than a standard CRP.

C-reactive protein rises in response to inflammation anywhere in the body. The "high-sensitivity" version of the test can detect much lower, chronic levels of inflammation than the standard CRP test used to check for acute infection: the kind of low-grade, ongoing inflammation that longevity-focused research links to cardiovascular and metabolic disease risk over time, rather than any single illness.

Where to compareOn the comparison page, 5 of the 9 blood tests and programs that list their markers include hs-CRP as standard (Everlab, Hemexa, i-screen, Listen Health and MediTests), and 1 sells it as an add-on (Bloody Good). Checked 3 Nov 2026.

Reflects average blood sugar levels over roughly the past 2–3 months, not a single point-in-time reading.

Glucose in the bloodstream attaches to haemoglobin inside red blood cells, and red blood cells live for about three months, so measuring what proportion of haemoglobin has glucose attached gives a running average of blood sugar exposure, rather than a single day's snapshot the way a standard glucose test does. It's the standard marker used to track metabolic health and diabetes risk over time.

Where to compareOn the comparison page, 8 of the 9 blood tests and programs that list their markers include HbA1c as standard (Everlab, ThriveRx, Bloody Good, Express Pathology, Hemexa, i-screen, Listen Health and MediTests). Checked 3 Nov 2026.

The standard cholesterol blood test: total cholesterol, LDL, HDL and triglycerides.

A lipid panel is the foundational cardiovascular screening test almost every provider on this site includes by default. It measures total cholesterol along with its main components: LDL ("bad" cholesterol), HDL ("good" cholesterol) and triglycerides (a type of fat circulating in the blood). It's usually the baseline that ApoB and Lp(a) sit alongside, rather than a replacement for either.

Where to compareOn the comparison page, 8 of the 9 blood tests and programs that list their markers include a lipid panel as standard (Everlab, ThriveRx, Bloody Good, Express Pathology, Hemexa, i-screen, Listen Health and MediTests). Checked 3 Nov 2026.

A group of tests covering hormones such as testosterone, oestrogen, thyroid hormones and cortisol, depending on the provider.

What's actually included under "hormone panel" varies more between providers than any other marker on this list, some cover a full thyroid + sex hormone + cortisol panel, others a narrower selection. Hormone levels shift naturally with age and are linked in research to energy, body composition, mood and metabolic health, which is why longevity-focused programs track them rather than leaving them to a standard GP check-up.

Where to compareOn the comparison page, 7 of the 9 blood tests and programs that list their markers include a hormone panel as standard (Everlab, ThriveRx, Bloody Good, Express Pathology, Hemexa, i-screen and Listen Health). Which hormones are included differs; each profile says. Checked 3 Nov 2026.

Measures the storage form of vitamin D circulating in the blood.

Vitamin D is made in the skin from sun exposure and obtained from a small number of foods, then stored in the blood in a form that's straightforward to measure directly. It's one of the most commonly tracked markers in general health testing (deficiency is widespread even in sunny climates) and is linked in research to bone, immune and metabolic health.

Where to compareOn the comparison page, 8 of the 9 blood tests and programs that list their markers include vitamin D as standard (Everlab, ThriveRx, Bloody Good, Express Pathology, Hemexa, i-screen, Listen Health and MediTests). Checked 3 Nov 2026.

A group of tests, usually ferritin, serum iron and transferrin saturation, that assess the body's iron stores.

"Iron studies" isn't a single number but a small panel of related tests that together show how much iron the body has stored and how efficiently it's being transported and used. Both deficiency and excess iron are relevant to long-term health, and iron studies are one of the more commonly abnormal results found in routine testing, which is why longevity panels typically include the full set rather than a single iron reading.

Where to compareOn the comparison page, 8 of the 9 blood tests and programs that list their markers include iron studies as standard (Everlab, ThriveRx, Bloody Good, Express Pathology, Hemexa, i-screen, Listen Health and MediTests). Checked 3 Nov 2026.

A biological age estimated from sugar structures (glycans) on IgG antibodies.

The company frames it around chronic inflammation. It isn't an epigenetic clock, so its result won't necessarily match one.

Where to compareSee biological age tests explained for how it compares with other tests.

A low-dose X-ray scan that measures bone density plus the split between fat mass, lean muscle and visceral fat.

Originally developed to measure bone density (still the clinical gold-standard for that), a DEXA scan also gives a detailed body-composition breakdown: how much of your weight is fat versus lean muscle, and how it's distributed, including visceral fat around the organs that a bathroom scale or BMI can't distinguish. It uses a very low dose of X-ray radiation and typically takes under 15 minutes. Most DEXA providers on this site don't require a GP referral.

Not every "DEXA scan" on offer includes the full body-composition breakdown. See BMD scan below for the narrower, bone-only version of the same technology.

Where to compareOn the comparison page, MeasureUp's bundle ($585) includes a DEXA scan. Checked 3 Nov 2026.

A dedicated bone-density scan, usually just the hip and lower spine, used to screen for osteoporosis, not a full body-composition breakdown.

A BMD scan uses the same DEXA (dual-energy X-ray absorptiometry) technology as a body-composition scan, but with a narrower focus: it measures bone mineral density at the hip and lumbar spine specifically, producing a T-score (compared against a healthy young adult) and a Z-score (compared against your own age group), the standard measurements used to screen for osteoporosis and fracture risk.

This is a genuinely different service to the whole-body DEXA scans marketed for body composition (fat mass, lean muscle, visceral fat) that longevity programs typically offer, even though the underlying machine is the same. A standalone BMD scan is narrower and often cheaper, and in Australia can be Medicare-rebated for eligible patients (for example, over 70, or with specific risk factors) via a GP referral, unlike most other tests on this site. If you want the fuller fat/muscle breakdown rather than just bone density, check directly whether a provider's "DEXA scan" includes body composition or is BMD-only, the two get marketed under the same name more often than they should.

Where to compareCheck each scan's profile on the comparison page for exactly what it measures.

A structural scan of the whole body, used to look for abnormalities across organs and tissue, usually needs a GP referral.

A whole-body MRI uses magnetic fields rather than radiation to produce detailed structural images across the body in a single session, rather than imaging one specific area the way a typical diagnostic MRI does. Unlike most other tests on this site, it more often requires a GP referral in Australia. Check each provider's own listing rather than assuming, since this varies.

Where to compareThe comparison page lists whole-body MRI from OneMRI ($2,990), Whole Body MRI on the Gold Coast ($2,995) and Prenuvo ($2,999), with GP referral status for each. Checked 3–5 Nov 2026.

The maximum amount of oxygen your body can use during intense exercise. It's one of the strongest predictors of cardiovascular fitness and, in research, of long-term mortality risk.

VO2 max measures how efficiently your body takes in and uses oxygen when exercising at maximum effort, expressed in millilitres of oxygen per kilogram of body weight per minute (mL/kg/min). It's measured most accurately in a lab via a graded treadmill or bike test with a metabolic cart analysing your breath, though many wearables (smartwatches, rings) also give an estimated VO2 max from heart-rate and pace data during regular exercise, a convenient estimate, not a lab-grade measurement, and the two can disagree.

Where to compareSee our research page for what one large study found about fitness and mortality risk. On the comparison page, MeasureUp's bundle ($585) includes a VO2 max test. Checked 3 Nov 2026.

A low-dose CT scan of the heart that measures calcified plaque in the coronary arteries and reduces it to a single score. It's one of the more direct ways to see early heart disease before symptoms show up.

A CAC scan is a low-dose CT scan focused on the heart, looking specifically for calcium deposits in the walls of the coronary arteries: a direct physical marker of atherosclerosis (plaque build-up), rather than an inferred risk factor like a cholesterol number. The result is expressed as an Agatston score: 0 means no detectable calcified plaque, and the score rises with the amount found, with commonly cited bands roughly at 1–99, 100–399 and 400+ used to describe low, moderate and high plaque burden. A score of 0 doesn't rule out all cardiovascular risk (soft, non-calcified plaque isn't picked up by this scan), and it isn't something people re-test frequently: it typically only makes sense to repeat after some years, not months.

It's a distinct test from a standard lipid panel or ApoB blood test. Those measure risk factors circulating in the blood, while a CAC scan looks directly at physical plaque that's already there. Some clinicians use blood markers to help decide who might benefit from a CAC scan, rather than treating the two as interchangeable. In Australia a CAC scan often needs a GP referral and involves a small dose of ionising radiation. Check each provider's own listing for both.

Where to compareOn the comparison page, HealthScreen's program includes a CT calcium score "if clinically indicated". Checked 3 Nov 2026.

A DNA test that estimates how "biologically old" your cells appear, based on chemical marks on your DNA, rather than your birth-certificate age.

Chemical tags called methylation marks build up on DNA in patterns that shift somewhat predictably with age. A DNA methylation "clock" estimates a biological age from those patterns, which can run ahead of or behind your actual age. This is a fundamentally different test from an ancestry or disease-risk DNA test. It isn't looking at your genetic code itself, but at how it's currently being chemically marked. Providers typically frame it as a way to track whether lifestyle changes shift the number over repeated tests, rather than a one-off diagnosis.

GrimAge and PhenoAge aren't separate tests, they're different scoring algorithms ("clocks") that can be run on the same DNA methylation sample. Earlier clocks (like the original Horvath clock) were built to predict chronological age closely; later ones like PhenoAge and GrimAge are instead calibrated against clinical health markers or mortality data, aiming to reflect health risk rather than just count years, which is why the same sample can sometimes produce a different-looking number depending which clock a provider uses. A provider's listing usually names which clock it runs; if it doesn't say, that's worth asking directly rather than assuming.

Where to compareThe comparison page lists 2 DNA and epigenetic tests: Elemental Health & Nutrition ($825) and Muhdo Health ($900). Some programs offer one as an add-on. Checked 3 Nov 2026. See also biological age tests explained.

A DNA methylation measure of how fast you're ageing now, rather than how old you are.

1.0 means one year of biological ageing per calendar year, and 1.2 means about 20% faster. It was developed by researchers at Duke and Otago from people tracked between ages 26 and 45.

Where to compareSee biological age tests explained for how it compares with other tests.

A second-generation epigenetic clock trained on lifespan and disease risk.

It has been described as consistently the strongest epigenetic predictor of mortality. That is a finding about populations, not a forecast for one person.

Where to compareSee biological age tests explained for how it compares with other tests.

A biological age built by Morgan Levine, in a blood version and a DNA version.

The blood version uses nine routine lab markers and your age. The DNA version (DNAm PhenoAge) uses 513 methylation sites. Same name, different tests.

Where to compareSee biological age tests explained for how it compares with other tests.

The length of the protective caps on chromosome ends, which shorten as cells divide.

It was an early biological age measure. Telomere tests report this one measure, while the newer clocks read many sites across the DNA.

Where to compareSee biological age tests explained for how it compares with other tests.

A biological age given for one body system, such as the heart, liver or kidneys.

These scores are newer than whole-body clocks, and they aren't a diagnosis.

Where to compareSee biological age tests explained for how it compares with other tests.

A gene involved in transporting cholesterol and fats around the body, including in the brain. It's one of the most-studied genes in ageing research.

APOE comes in three common variants: e2, e3 and e4. Research has linked the e4 variant to a higher population-level risk of late-onset Alzheimer's disease and cardiovascular disease, though carrying e4 doesn't guarantee developing either condition, and not carrying it doesn't rule them out, genetics is one part of a much larger picture that also includes lifestyle, environment and other risk factors. Because of how sensitive this particular result can feel, some providers offer it as an opt-in add-on rather than a default part of a DNA panel, and genetic counselling is worth considering before or after testing for it.

Where to compareWe don't list a standalone APOE test on the comparison page. If you're considering one, it's worth talking to your GP or a genetic counsellor first.

A gene involved in processing folate (vitamin B9) and regulating homocysteine. A popular inclusion in consumer DNA panels, but a more contested one clinically.

Certain MTHFR variants (commonly labelled C677T and A1298C) are associated with reduced activity of an enzyme involved in folate metabolism and homocysteine regulation. It's a popular inclusion in consumer DNA and longevity panels, but mainstream clinical guidance is more measured than some wellness marketing suggests: major medical bodies generally don't recommend routine MTHFR testing or treatment decisions based on genotype alone, since the link between common variants and real-world health outcomes is weaker and more contested than often portrayed.

Where to compareWe don't list a standalone MTHFR test on the comparison page.