📐 Scientific Methodology · LongevLife™ · Updated June 2026

LongevLife Methodology

How LongevLife calculates Vitality Score™, estimates biological age, selects research and builds protocols. Full scientific transparency.

Core Methodology Principles

Evidence-First

Every claim requires a peer-reviewed DOI from PubMed-indexed journals. No claim without citation. No citation without DOI.

Zero Fabrication

No invented studies, journals, statistics or quotes. If a study cannot be verified on PubMed - it is excluded.

Longevity vs Clinical

LongevLife distinguishes clinical normal ranges from Longevity optimal targets. These are explicitly labeled on every page.

Epistemic Humility

Evidence strength is labeled: Strong (meta-analysis/RCT) · Moderate (small RCT) · Preliminary (animal/correlation). Users know the difference.

Bilingual Parity

All scientific content exists in Hebrew and English. The same accuracy standard applies to both languages.

Regular Updates

Content is reviewed against new publications. Update date is visible on every article page.

Vitality Score™ Calculation Methodology

What It Measures

Vitality Score™ measures current longevity vitality - not fixed biological age. It reflects actionable lifestyle factors that science has linked to mortality risk and biological aging rate (DunedinPACE).

Calculation Formula

Vitality Score™ Formula - v1.2

VS = (Sleep × 0.25) + (Activity × 0.25) + (Metabolism × 0.20)
+ (Nutrition × 0.15) + (Mental × 0.10) + (Biomarkers × 0.05)

// Each domain scored 0-100. Weights reflect mortality impact per domain per peer-reviewed meta-analyses.
// Sleep and Activity each weighted 25% based on JAMA 2009 (VO2max) and Nature Communications 2021 (sleep)

Domain Scoring Basis

Sleep (25%): Hours per night, consistency, subjective quality. Based on Sabia et al. Nature Communications 2021 - sleep below 6 hours at age 50 raises dementia risk 30%.
Physical Activity (25%): Minutes of Zone 2 per week, strength training frequency. Based on Kodama et al. JAMA 2009 - each 1 MET = 13% mortality reduction.
Metabolism (20%): Self-reported HbA1c (if known), energy after meals, weight stability. Based on Lancet 2011 meta-analysis n=310,458.
Nutrition (15%): Omega-3 sources, sugar intake, Mediterranean adherence. Based on VITAL trial NEJM 2019.
Mental/Stress (10%): Chronic stress level, relaxation practices, HRV if known. Based on Chandrasekhar et al. 2012.
Known Biomarkers (5%): Self-reported Vitamin D, HbA1c, Ferritin status if available.

Important: Vitality Score™ is a self-reported assessment. It becomes significantly more accurate when combined with actual blood biomarker results. Users with blood test data should enter values in the Biomarkers section for improved precision.

Biological Age Estimation Methodology

LongevLife does not claim to measure clinical biological age. The platform presents four validated scientific methods and explains their differences:

PhenoAge (Levine et al., 2018) - 9 blood biomarkers. Users can calculate their own PhenoAge using actual blood values at /calc-phenoage (coming soon).
GrimAge (Lu et al., 2019) - DNA methylation. Requires third-party genetic test ($200-400). LongevLife links to established providers.
DunedinPACE (Belsky et al., 2022) - Pace of aging. Also requires methylation test.
VO2max Age - Calculated from Uth-Sørensen formula (2004) using resting heart rate. Available free at /calc-vo2max.

The LongevLife Biological Age estimate displayed in the Vitality Score dashboard is an approximation based on VS score distribution - not a clinical measurement. It should be interpreted as directional only.

Protocol Design Methodology

Each LongevLife protocol follows a structured evidence review:

Question definition: "What intervention has the highest impact on [outcome]?"
Literature search: PubMed search for meta-analyses and RCTs. Priority: systematic reviews > RCTs > prospective cohorts > observational.
Evidence grading: Strong / Moderate / Preliminary - labeled explicitly in each protocol.
Dose selection: Based on the studied dose in the primary cited study - not manufacturer recommendations.
Timeline: Based on study duration for measurable outcomes.
Safety check: Known contraindications and drug interactions are listed.

What LongevLife Methodology Does NOT Include

Proprietary algorithmic "secrets" that override published science
Unverified biohacking claims
Testimonial-based recommendations
Commercial sponsor-influenced content
Recommendations outside peer-reviewed evidence

Version History

v1.0 - January 2025: Initial Vitality Score methodology
v1.1 - March 2025: Added Biomarkers domain (5%)
v1.2 - June 2026: Refined Metabolism weighting, added bilingual parity

Methodology last reviewed: June 2026. Questions or feedback: hello@longevlife.com