Two elderly people enjoying a moment on a park bench, symbolizing extended lifespans and the passage of time within a century.A century, by definition, is a span of 100 years – a significant chunk of time in human history. As we navigate the 21st century, questions about time, life, and longevity become increasingly pertinent. While a century marks a fixed duration on the calendar, the very concept of a human lifespan within this century is proving to be more fluid and potentially record-breaking than ever before. The number of individuals living past the age of 100 has seen a consistent rise over recent decades, reaching almost half a million people globally.
However, the realm of “supercentenarians,” those who surpass 110 years, remains far less populated. Jeanne Calment of France, the longest-lived person documented, reached 122 years before her passing in 1997. Currently, Kane Tanaka of Japan holds the title of the world’s oldest living person at 118 years old.
Groundbreaking research from the University of Washington suggests that such extreme longevity is not an anomaly but a trend poised to continue its slow ascent throughout the 21st century. Projections indicate that reaching a lifespan of 125 years, and possibly even 130 years, is within the realm of possibility within this century.
“People are inherently interested in human limits, whether it’s in athletic achievements, space exploration, or the duration of life itself,” explains lead author Michael Pearce, a statistics doctoral student at UW. “Our research aims to quantify the likelihood of individuals reaching various extreme ages within this century.”
Understanding the boundaries of human lifespan carries significant implications. It informs governmental and economic strategies, shapes healthcare policies, and influences individual decisions regarding personal health and lifestyle. Therefore, discerning what is probable, and even possible, in terms of longevity holds relevance across all societal levels as we progress through this century.
This new study, published in Demographic Research, employs statistical modeling to delve into the extremes of human life. Amidst ongoing advancements in aging research, potential breakthroughs in medicine and science, and the relatively small number of individuals verified to have lived beyond 110, experts are engaged in a debate regarding the potential upper limits of human lifespan, often termed the maximum reported age at death. While some scientists argue for a natural limit imposed by disease and cellular degradation, others contend against a definitive cap, citing the remarkable cases of record-breaking supercentenarians.
Pearce and Adrian Raftery, a sociology and statistics professor at UW, adopted a different perspective. Their research posed the question: what is the maximum individual human lifespan achievable anywhere in the world before the close of the 21st century? Utilizing Bayesian statistics, a prevalent tool in modern statistical analysis, the researchers estimated that the current world record of 122 years is almost certain to be surpassed. Furthermore, they project a strong probability of at least one person living between 125 and 132 years within this century.
To ascertain the probability of living beyond 110 – and to what advanced age – Raftery and Pearce consulted the most recent iteration of the International Database on Longevity, maintained by the Max Planck Institute for Demographic Research. This comprehensive database meticulously tracks supercentenarians from 10 European nations, along with Canada, Japan, and the United States.
Applying a Bayesian approach to probability estimation, the UW research team developed projections for the maximum reported age at death across all 13 countries spanning from 2020 to 2100.
Their key findings include:
- A near certainty (almost 100% probability) that the existing record for maximum reported age at death — Jeanne Calment’s 122 years, 164 days — will be broken within this century.
- A strong probability (99%) of an individual living to 124 years old, and even a significant probability (68%) of reaching 127 years old.
- The possibility of even greater longevity exists, but with decreasing likelihood, with a 13% probability of someone living to age 130 within this century.
- It is deemed “extremely unlikely” for anyone to reach the age of 135 in this century.
Supercentenarians remain exceptional individuals, and the probability of surpassing the current age record is contingent on a significant increase in their numbers. With the global population continuing to expand throughout this century, this scenario is not improbable, according to researchers.
Even with population growth and advancements in healthcare within this century, individuals achieving extreme longevity remain a select group. Raftery notes that there is an observed plateau in mortality rates after a certain age. In essence, an individual reaching 110 years old has approximately the same probability of living another year as someone aged 114, which is roughly one-half.
“Regardless of their age beyond 110, the mortality rate remains consistent,” Raftery explains. “These individuals have overcome numerous life challenges, including diseases. Their eventual deaths are attributed to factors somewhat independent of those affecting younger populations.
“This cohort represents a highly select group of remarkably robust individuals within the broader population of each century.”
This research was supported by funding from the National Institute for Child Health and Human Development, furthering our understanding of human life within the context of a century and beyond.
For further information, please contact Pearce at [email protected] or Raftery at [email protected].
