Scans & Imaging

What it measures: A non-contrast CT scan quantifying calcified plaque in the coronary arteries, reported as an Agatston score.

Why it matters: Calcified plaque is a direct, visible marker of existing atherosclerotic burden — it doesn't estimate risk from risk factors, it images the disease itself.

Evidence: Detrano R, Guerci AD, Carr JJ, et al. (MESA study) "Coronary Calcium as a Predictor of Coronary Events in Four Racial or Ethnic Groups." N Engl J Med 2008;358:1336–1345 — in 6,722 adults without known cardiovascular disease, a doubling of the calcium score increased risk of a major coronary event by 15–35% across four racial/ethnic groups, independent of traditional risk factors. CAC scoring is now incorporated into the 2018 ACC/AHA cholesterol guideline as a formal decision aid: in intermediate-risk patients, a CAC of 0 can support deferring statin therapy, while a high score supports intensifying it. Arguably the single best-evidenced "extra" test on this site.

Detrano R, et al. N Engl J Med. 2008. PubMed: PMID 18367736 · Full cost breakdown & who it's for →

What it measures: Dual-energy X-ray absorptiometry. Two distinct uses are usually bundled under one scan: (1) bone mineral density (its original, guideline-endorsed use), and (2) whole-body composition — fat mass, lean mass, and a modelled estimate of visceral adipose tissue (VAT).

Why it matters: Osteoporosis is common, often silent until fracture, and treatable. Visceral fat drives insulin resistance, dyslipidaemia, and hepatic inflammation via portal free-fatty-acid and cytokine release.

Evidence: The bone density use case is genuinely Strong — well-validated fracture-risk prediction, guideline-endorsed screening in postmenopausal women and older men. The body-composition use case marketed in longevity packages is weaker: visceral fat measured directly (e.g. by CT) is an independent predictor of all-cause mortality in men, but DEXA's VAT figure is a modelled estimate from 2D imaging, not a direct volumetric measurement, and has acknowledged limits distinguishing visceral from other trunk fat depots compared with CT/MRI. It is a reasonable, low-radiation proxy for tracking body composition change over time, but the specific "VAT number" from DEXA should be read as an estimate, not a precise clinical figure.

Visceral fat and mortality: PubMed: PMID 16571861 (Kuk JL, et al., "Visceral fat is an independent predictor of all-cause mortality in men") · Full cost breakdown & bone density vs body composition →

What it measures: Coronary CT angiography (CCTA) uses contrast to visualise the coronary lumen and both calcified and non-calcified ("soft") plaque; cardiac MRI assesses structure, function, and tissue characteristics (e.g. scar, fibrosis).

Why it matters: CCTA can detect non-calcified plaque that a calcium score misses entirely, including in younger patients who haven't yet developed calcification.

Evidence: CCTA is well validated for evaluating symptomatic chest pain (the SCOT-HEART trial demonstrated improved diagnostic certainty and reduced coronary death/MI at 5 years when CCTA was added to standard care) and is increasingly used for further risk refinement after an abnormal or borderline CAC score. It is not established as a first-line, routine screening tool for asymptomatic, average-risk adults — it carries a contrast and (for CT) radiation exposure that calcium scoring does not, and the evidence base is strongest in symptomatic or higher-risk populations rather than as a general population screen.

What it measures: Ultrasound assessment of the carotid artery wall thickness and any plaque, sometimes marketed as a "vascular age" or stroke-risk test.

Why it matters: Carotid plaque reflects systemic atherosclerosis and, if severe (high-grade stenosis), can directly cause stroke.

Evidence: The US Preventive Services Task Force gives screening for asymptomatic carotid artery stenosis a "D" (against) recommendation — moderate certainty that the harms (unnecessary downstream imaging/procedures from false positives, procedural complications from unindicated intervention) outweigh the benefits, and no externally validated method reliably identifies which asymptomatic adults are actually at increased stroke risk from incidental carotid findings.

USPSTF Recommendation Statement, JAMA 2021. PubMed: PMID 34058106

What it measures: Full abdominal MRI, sold in some longevity packages as a way to directly image visceral fat and screen abdominal/pelvic organs for incidental disease.

Why it matters: MRI-measured visceral fat volume is the research gold standard (more accurate than DEXA), and organ imaging can occasionally catch unexpected pathology.

Evidence: Large research cohorts (e.g. the UK Biobank imaging sub-study) use abdominal MRI to quantify visceral fat precisely, but this is a research protocol, not a validated clinical screening pathway for asymptomatic adults. Used as a general "screen everything" tool, abdominal MRI has a high rate of incidental findings (benign cysts, indeterminate nodules) that generate follow-up imaging, biopsies, and anxiety without a proven net mortality or morbidity benefit — there is no professional guideline recommending whole-abdomen MRI screening in asymptomatic average-risk adults.

What it measures: Structural brain imaging, marketed in some executive-health packages as an early screen for silent stroke, aneurysm, or neurodegeneration.

Why it matters: Can detect small vessel disease, silent infarcts, and structural abnormalities that are genuinely clinically important when found in a symptomatic patient.

Evidence: In asymptomatic adults, screening brain MRI has a well-documented high rate of incidental findings (the reported incidence of incidental findings on research brain MRI is commonly cited in the 2–8% range depending on definition and age), the large majority of which are benign or of uncertain significance, generating follow-up scans and anxiety without a demonstrated pathway to improved outcomes for the average screened person. No major guideline body recommends brain MRI as a general population longevity or dementia-risk screen.