Humans have an obsession with not dying, and have dedicated their collective brainpower to the scientific task of abolishing death – yet in spite of our greatest efforts, people are not living any longer than they were 20 years ago, suggesting we may have hit the natural ceiling of our lifespan.
Appearing in the journal Nature, a new study has found that while average life expectancies are still rising across the world, the maximum age reached by the planet’s oldest people seems to have plateaued in the mid 1990s.
To conduct their research, the study authors analyzed data recorded in the Human Mortality Database, which contains information on mortality rates in more than 40 countries. Unsurprisingly, they discovered that the proportion of people successfully reaching old age without expiring has been increasing steadily since 1900, which they attribute to the ever-increasing quality of healthcare.
However, they then looked at data for the US, France, Japan, and the UK, which are the four countries with the highest number of supercentenarians – meaning those who live to be more than 110. In doing so, they found that while the maximum age of the oldest people in these countries rose steadily until 1995, this trend ground then to a halt, with the age of death of the oldest person decreasing by 0.28 years per year thereafter.
Based on their findings, the researchers calculate the maximum natural human lifespan to be 115 years, although that is not to say that “unnatural” ages won’t be reached in the future, if science achieves its goal of doing away with aging.
In a statement, study co-author Jan Vijg explained that “while it's conceivable that therapeutic breakthroughs might extend human longevity beyond the limits we've calculated, such advances would need to overwhelm the many genetic variants that appear to collectively determine the human lifespan. Perhaps resources now being spent to increase lifespan should instead go to lengthening healthspan – the duration of old age spent in good health.”
Though the researchers believe the odds of any person living to 125 years old to be less than one in 10,000, there are still occasional anomalies. The oldest person on record is a French woman named Jeanne Calment, who died in 1997 at the age of 122, while a man in Indonesia currently claims to be 145 years old – though this still needs to be verified.