# What is Longevity?

Longevity means extending the healthy years of life, not just the total years. Researchers distinguish lifespan (how long you live) from healthspan (how many of those years you live free of chronic disease and disability), a gap that often runs 10 to 20 years. Lifestyle does most of the work: corrected estimates put the genetic share of lifespan well below 10 percent, and possibly around 50 percent only when intrinsic mortality is isolated.

The science of living longer, healthier, and more fulfilling lives

## On this page

- What Does Longevity Actually Mean?
- Healthspan vs Lifespan: What's the Difference?
- Why Should You Care About Longevity?
- Where Is Longevity Science Right Now?
- How Do You Get Started?

## FAQ

- Can anyone improve their longevity?
- At what age should I start thinking about longevity?
- Is longevity science the same as anti-aging?
- What's the single most important thing I can do for longevity?

## Sources

- López-Otín C, Blasco MA, Partridge L, Serrano M, Kroemer G. (2023). Hallmarks of aging: An expanding universe. Cell. https://doi.org/10.1016/j.cell.2022.11.001
- Ruby JG, Wright KM, Rand KA, et al.. (2018). Estimates of the Heritability of Human Longevity Are Substantially Inflated due to Assortative Mating. Genetics. https://doi.org/10.1534/genetics.118.301613
- Herskind AM, McGue M, Holm NV, Sørensen TI, Harvald B, Vaupel JW. (1996). The Heritability of Human Longevity: A Population-Based Study of 2872 Danish Twin Pairs Born 1870-1900. Human Genetics. https://doi.org/10.1007/BF02185763
- Scott AJ, Ellison M, Sinclair DA. (2021). The economic value of targeting aging. Nature Aging. https://doi.org/10.1038/s43587-021-00080-0
- Xu J, Murphy SL, Kochanek KD, Arias E. (2026). Mortality in the United States, 2024. NCHS Data Brief. https://www.cdc.gov/nchs/products/databriefs/db548.htm
- Shenhar B, Pridham G, De Oliveira TL, Raz N, Yang Y, Deelen J, Hägg S, Alon U (Science 391(6784):504-510, 29 Jan 2026, PMID 41610249). (2026). Heritability of intrinsic human life span is about 50% when confounding factors are addressed. Science. https://doi.org/10.1126/science.adz1187

_Full guide: https://usa-longevity.com/en/guide/what-is-longevity_

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_Canonical: https://usa-longevity.com/en/guide/what-is-longevity · Part of Longevity Cities · Updated 2026-05-18_