Longevity Science
Longevity Science • December 2025

The Science of Living Longer: What Actually Works

An evidence-based 2025 playbook for extending healthy lifespan. The 8 highest-impact moves, the risk spectrum, and the hierarchy of both protective and harmful factors.

TL;DR – 8 Highest-Impact Actions

Do these and you capture ~80–90% of what modern science knows about extending healthy lifespan. Negative numbers = lower risk (longer life); positive = higher risk.

Years Added Estimation Method: for a 40-year-old (~80 years life expectancy, ~40 remaining), estimates use actuarial/CDC/Lee-Carter style models adjusted for relative risk reductions. Example: ~−50% mortality ≈ +14–20 years (halves death rate over remaining life). Ranges reflect age/sex variability; cumulative for top 8 ≈ +16–25 years.

Fitness breakdown: 1a = jump from sedentary to moderate (−45% to −60%). 1b = additional −20% to −35% moving from moderate to elite (total ≈ −80% vs sedentary). Additive for full impact.

Rank Action Minimum Effective Dose / Target Mortality Change
vs Average Person		 Est. Years Added
(for 40yo)		 Evidence
1a Achieve moderate cardiorespiratory fitness (from sedentary) 150–300 min/week moderate or 75–150 min vigorous cardio −45% to −60%
(vs sedentary)		 +4–7 years ★★★★★
1b Push from moderate to elite fitness Top 10–20% VO₂ max for age/sex (add HIIT/strength) −20% to −35% additional
(vs moderate)		 +6–7 years
additional		 ★★★★★
2 Never smoke / quit immediately Zero cigarettes −65% +14–17 years ★★★★★
3 Zero or near-zero alcohol <1 standard drink per month −15% +1.5–3 years ★★★★★
4 Strong social relationships Weekly meaningful contact + low loneliness −45% +5–9 years ★★★★★
5 Cultivate a strong sense of purpose Volunteering, ikigai, spiritual practice, or clear life goals −22% +3–5 years ★★★★★
6 Resistance train + preserve muscle 2–3 full-body sessions/week + ≥1.6 g/kg protein −35% +4–7 years ★★★★★
7 Plant-rich Mediterranean diet + generous EVOO Vegetables, legumes, nuts, fish + ≥4 tbsp extra-virgin olive oil/day −25% +4–7 years ★★★★★
8 Sleep 7–9 h with excellent hygiene Consistent schedule, dark/cool room −18% +2.5–4 years ★★★★★

High-impact extras

  • Frequent sauna (4–7×/week) → −24% (+3–5 years)
  • Mild calorie restriction or 16:8 TRE → −15% (+1.5–3 years)
  • Omega-3 (1–2 g EPA+DHA if low fish) → −8% (+0.5–1.5 years)
  • Glucosamine 1,500 mg + creatine 5 g → −15 to −30% (+1.5–4 years, emerging)

Avoid / mitigate

  • Any regular alcohol, heavy drinking
  • Sedentary living (bottom 20% VO₂ max)
  • Ultra-processed foods, chronic loneliness
  • Smoking (current or relapse)
Based on these evidence-based estimates for a 40-year-old (~40 years remaining), doing all 8 actions adds ~16–25 healthy years. This is a conservative actuarial aggregate (CDC/GDB, Lee-Carter style), not a straight sum (~40–60 years would overestimate). It accounts for synergies (e.g., exercise + social ties amplify by ~20–30%) and diminishing returns (largest jumps come from the first changes).

Visualization

2025 Longevity Spectrum

Green = protective. Red = harmful. Values are % change in all-cause mortality vs today’s average moderately active adult.

Ranked Longevity Hierarchy

Protective factors (negative % = lower risk)
Rank Factor Best Evidence-Based Practice All-Cause Mortality
Reduction		 Est. Years Added
(for 40yo)		 Strength of Evidence Key References
1a Cardiorespiratory fitness Achieve moderate fitness; VO₂ max >35 mL/kg/min (men), >30 (women) −50% to −80% +9–13 years High (RCTs + cohorts) [1,2]
1b Push toward elite fitness Top 10–20% VO₂ max for age/sex ≈−80% (≈5× lower than sedentary) +10–14 years total High [1,2]
2 Never smoking / quit immediately Lifelong non-smoker −50% to −70% +14–17 years High [3]
3 Alcohol Lifelong abstention or <1 drink/month −8% to −17% vs any regular use +1–2 years High (Mendelian + cohorts) [4,5]
4 Strong social relationships High social integration / low loneliness −30% to −50% +5–9 years High [6]
5 Sense of purpose & meaning in life High ikigai / eudaimonic well-being (volunteering, goals, etc.) −15% to −25% +3–5 years High [7–10]
6 Muscle mass & strength Resistance train 2–3×/week + ≥1.6 g/kg protein −20% to −40% +4–7 years High [11]
7 Mediterranean / plant-rich pattern High adherence (vegetables, legumes, nuts, fruit, fish) −18% to −25% +4–7 years High (RCT + cohorts) [12,13]
8 Extra-virgin olive oil (EVOO) ≥3–5 tablespoons (40–70 g) per day −17% to −23% +3–5 years High (RCT + cohorts) [14–16]
9 Frequent sauna bathing 4–7 sessions/week, 15–20 min at 80–100 °C −24% all-cause, −40% CVD +3–5 years Moderate-High [17]
10 Optimal sleep 7–9 h/night, high quality, consistent schedule −12% to −20% +2.5–4 years High [18]
11 Calorie restriction / TRE 10–20% restriction or 16:8 eating window −10% to −20% +1.5–3 years Moderate [19]
12 Omega-3 (EPA+DHA) 1–2 g/day if low fish intake −7% to −10% +0.5–1.5 years Moderate [20]
13 Education (additional years) Each extra year of schooling −2% to −3% per year +0.5–1 year per year High [21]
14 Vitamin D (correct deficiency) Serum 25(OH)D ≥40–60 ng/mL −5% to −10% +0.5–1.5 years Moderate [22]
15 Glucosamine 1,500 mg/day −15% to −39% +2–4 years Low-Moderate [23]
16 Creatine ≥3–5 g/day −15% +1.5–3 years Low-Moderate [24]

Ranked Negative Factors

Harmful exposures (positive % = higher risk)
Rank Factor Typical Harmful Exposure All-Cause Mortality Increase Est. Years Lost (for 40yo) Strength of Evidence Key References
1 High Ultra-Processed Food Intake ≥20% of daily calories from UPF +10% to +20% −1 to −2 years Moderate-High [25]
2 Any Regular Alcohol Light-moderate regular drinking (>1 drink/month) +15% −1 to −2 years High (Mendelian + cohorts) [4,5]
3 Loneliness / Social isolation Chronic low social ties +26% to +50% −3 to −6 years High [6]
4 Air Pollution (PM2.5) ≥10 µg/m³ annual average +8% to +10% −0.5–1.5 years High [26]
5 True Sedentary / Low Fitness Bottom 20% VO₂ max (<26 mL/kg/min men, <20 women) +100% to +130% −9–13 years High (RCTs + cohorts) [1,2]
6 Heavy Alcohol ≥3 drinks/day or binge patterns +100% −9–13 years High [4,5]
7 Current Smoking Daily cigarette use +110% to +180% −14–17 years High [3]

Comprehensive Evidence Review (December 2025)

1. Cardiorespiratory Fitness

Largest modifiable lever: moving from sedentary to moderate cuts mortality 45–60%; elite adds 20–35% more (≈5× lower vs sedentary). Cohorts of 122k (JAMA Netw Open 2018), 750k veterans (Mayo 2023), meta-regression >2M people.

2. Smoking Cessation

Never-smokers show ~65% lower all-cause mortality; quitting rapidly converges toward never-smoker risk in 10–15 years. (Surgeon General 2024; Thun NEJM 2013).

3. Alcohol

MR and GBD analyses: no safe threshold. Near-zero intake (<1 drink/mo) ≈15% lower mortality vs light/moderate drinkers; heavy use doubles risk via liver, cancer, CVD. (GBD 2024 Alcohol; Biddinger Nat Med 2024).

4–5. Social Relationships & Purpose

High social integration ≈45% reduction; loneliness increases risk 26–50%. High purpose adds ~22% reduction via lower inflammation and better behaviors. (Holt-Lunstad 2015; Alimujiang 2024).

6. Muscle Mass & Strength

Resistance training/strength preservation linked to ~35% lower mortality; grip strength outpredicts cholesterol/BP. (Li BJSM 2023, 1.9M participants).

7–8. Mediterranean Pattern + EVOO

High adherence reduces risk 18–25%; ≥4 tbsp/day extra-virgin olive oil gives independent ~23% benefit. UPF raises risk 10–20% per 10% intake. (PREDIMED re-analysis; BMJ 2024 UPF).

9. Sauna Bathing

4–7 sessions/week: −24% all-cause and −40% CVD mortality, mimicking exercise-induced cellular protection. (Laukkanen JAMA Intern Med 2018).

10. Sleep

7–9 hours with good hygiene reduces mortality 12–20%; U-shaped risk outside that band. (Yin J Am Heart Assoc 2023; 1.6M participants).

Emerging Factors

Mild calorie restriction or 16:8 TRE (~15%); omega-3 (1–2 g EPA+DHA) ~8% if low fish; glucosamine/creatine 15–30%; added education 2–3%/yr; correcting vitamin D deficiency 5–10%; lowering PM2.5 by 10 µg/m³ cuts 8–10% risk.

References (December 2025)

  1. Mandsager K et al. JAMA Netw Open 2018 (fitness)
  2. Kokkinos P et al. Mayo Clin Proc 2023 (fitness)
  3. Thun MJ et al. NEJM 2013 (smoking)
  4. GBD 2024 Alcohol Collaborators (preprint)
  5. Biddinger KJ et al. Nat Med 2024 (alcohol MR)
  6. Holt-Lunstad J et al. Perspect Psychol Sci 2015 (social)
  7. Alimujiang A et al. Am J Epidemiol 2024 (purpose)
  8. Hill PL et al. Psychol Sci 2014 (purpose)
  9. Cohen R et al. JAMA Netw Open 2023 (purpose/well-being)
  10. Boyle PA et al. Arch Gen Psychiatry 2010 (purpose)
  11. Li R et al. Br J Sports Med 2023 (muscle strength)
  12. Estruch R et al. NEJM 2018 (Mediterranean diet)
  13. Trichopoulou A et al. NEJM 2003 (Mediterranean diet)
  14. Guasch-Ferré M et al. JAMA Intern Med 2022 (EVOO)
  15. Guasch-Ferré M et al. J Am Coll Cardiol 2020 (olive oil)
  16. Martínez-González MA et al. Circulation 2019 (EVOO)
  17. Laukkanen T et al. JAMA Intern Med 2018 (sauna)
  18. Yin J et al. J Am Heart Assoc 2023 (sleep)
  19. Redman LM et al. Cell Metab 2018 (calorie restriction)
  20. Bhatt DL et al. NEJM 2023 (omega-3)
  21. Licher S et al. Lancet Public Health 2024 (education)
  22. Zhang Y et al. BMJ 2020 (vitamin D)
  23. King DE et al. Arthritis Rheumatol 2020 (glucosamine)
  24. Wu SH et al. Nutrients 2021 (creatine)
  25. Lane MM et al. BMJ 2024 (ultra-processed foods)
  26. GBD Risk Factors 2023/24 (air pollution)

Bottom Line

Implementing the top 8 actions moves you from the 50th percentile of lifespan into the top 1–5%, adding 12–20 vibrant years while slashing risks for heart disease, cancer, dementia, and frailty. Layer in the high-impact extras and avoid the negatives (smoking, sedentary living, heavy alcohol) to prevent the majority of premature deaths.