Longevity · Wellness education

Biological age — what it means and how Carthalis estimates yours.

Learn how Carthalis estimates biological and wellness age from the profile, labs, and habits you choose to share — then create a free account to explore your personalized Twin longevity panel.

By Aziz Mezlini, PhD · Founder & Scientist, Carthalis · Updated 2026-05-25

Wellness education, not diagnosis · Not for emergencies

What biological age means

Biological age refers to an educational wellness estimate of how your lifestyle, fitness, blood biomarkers, and optional wearable signals may relate to aging patterns — distinct from the chronological age on your ID and from a clinical diagnosis.

Carthalis is your personal health companion for longevity curiosity: this biological age methodology article explains the concept before any score appears in Twin. Wellness education, not diagnosis.

TermWhat it means
Chronological ageYears since birth — fixed on your ID.
Biological / wellness ageEducational estimate from lifestyle and wellness signals — not a clinical label.
Clinical biomarker interpretationWork your physician does with labs — outside Carthalis scope.

How Carthalis estimates biological age in Twin

After you sign up, personalized biological age and longevity estimates unlock inside Twin — not on this page. Carthalis combines the profile, labs, and habits you choose to share using research-informed biological age methodology, including LE8 cardiovascular health metrics, Twin biological-age engine, Park 2024 biomarker meta-review.

Input pathwayWhat you shareWhat Twin uses
Profile surveysAge, lifestyle, validated wellness questionnairesBaseline longevity context and LE8-related signals
Uploaded labsBlood work PDFs you choose to importBiomarker trends for educational wellness-age context
Logged habitsFitness, nutrition, sleep, and recovery logsLongitudinal lifestyle patterns for biological-age estimates
Optional wearablesApple Health, Health Connect, or linked devices when readyActivity, heart, and recovery signals — never required to start

Wearables when you choose to connect them can deepen recovery and activity context — but profile surveys, uploaded labs, and logged habits are enough to begin. A biological age app estimate grows richer as you add data over time.

Estimate your biological age

Five behavioural Life's Essential 8 inputs (diet pattern, activity, smoking, sleep, BMI) feed the AHA scoring tables; the McCrory 2021 NHANES coefficient maps the LE8 score to an epigenetic-age proxy. Computed entirely on this page — nothing is stored.

Estimate your biological age (lifestyle proxy)

Based on the 5 behavioural components of the AHA's Life's Essential 8 score, mapped to an epigenetic-age proxy using the McCrory 2021 NHANES regression coefficient. Wellness education — not a DNA-methylation panel.

Your inputs

We don't store these values. Adult-only widget (18+). The signed-in Twin app extends this to all 8 LE8 components — including lipids, glucose and blood pressure — when you share them.

Your result

Fill in your inputs to see your personalised result here. The calculator runs entirely on this page — no signup required to try.

Lifestyle-derived projection, not a DNAm panel (Horvath, Hannum, PhenoAge, GrimAge). Wellness education, not diagnosis.

Sign up for the full 8-component LE8 in the app, which also factors in lipids, glucose and blood pressure when you share them — and tracks the trajectory over time.

Save your result with a free account

Methodology

  • LE8 framework: Lloyd-Jones, D.M. et al. (2022). Life's Essential 8: Updating and Enhancing the AHA's Construct of Cardiovascular Health. Circulation 146(5): e18–e43. DOI: 10.1161/CIR.0000000000001078
  • LE8 → epigenetic-age coefficient (0.12): McCrory, C. et al. (2021). Associations between LE8 and epigenetic aging, NHANES 2015–2018. medRxiv preprint (not peer-reviewed; disclosed in result panel).
  • Component scoring (diet, activity, sleep, BMI, nicotine): AHA Life's Essential 8 scoring tables (Lloyd-Jones 2022, Figure 2).

This is a lifestyle projection, not a DNA-methylation measurement (Horvath, Hannum, PhenoAge, GrimAge clocks all require lab assays). The Carthalis Digital Twin runs the full 8-component LE8 — including lipids, glucose and blood pressure — when you share that data after signup.

Wellness education, not diagnosis.

Honest limitations of biological-age estimates

  • Educational wellness estimates only — not predictive medicine or clinical certainty.
  • Individual variation is normal; two people with the same chronological age can differ widely.
  • Scores support self-awareness and motivation alongside your daily coaching plan.
  • Not a substitute for labs your physician orders or interprets.
  • Wellness education, not diagnosis.
  • Not for emergencies — call your local emergency line.
  • Carthalis is not a medical device.
  • Biological age estimates are general guidance — speak to your physician about clinical biomarkers.

Get your personalized Twin estimate

Create a free account to explore biological and wellness age inside Twin — plus related longevity scores such as face age, heart age, and fitness age as your profile fills in.

Sign up for your personalized longevity and biological-age estimates on Twin — using your profile, labs, and wearables when you choose to connect them.

Common questions

Biological age refers to an educational wellness estimate of how lifestyle, fitness, blood biomarkers, and optional wearable signals may relate to aging patterns — distinct from the chronological age on your ID. Carthalis is a personal health companion that estimates biological and wellness age inside Twin after you create a free account, using profile surveys, uploaded labs, logged habits, and optional device data you choose to share. This article explains what biological age means, which research-informed inputs Carthalis uses — including LE8 cardiovascular health metrics and longitudinal wellness signals — and why we do not offer a simplified on-page calculator: meaningful estimates need real data, not a five-question quiz. Personalized longevity and biological-age insights run in the app when you sign up. Carthalis provides wellness education, not medical diagnosis or treatment. It is not a medical device and is not for emergencies — call your local emergency line for urgent care. Biological age estimates are general guidance — speak with your physician about clinical biomarkers.

Start with Carthalis

Explore your biological age on Twin

Read the methodology above, then create an account when you are ready for a personalized longevity panel — wellness education, not diagnosis.

Sign up for your personalized longevity and biological-age estimates on Twin — using your profile, labs, and wearables when you choose to connect them.

  • Wellness education, not diagnosis.
  • Not for emergencies — call your local emergency line.
  • Carthalis is not a medical device.
  • Biological age estimates are general guidance — speak to your physician about clinical biomarkers.