Advances in medicine and technology are enabling us humans to live to an ever-increasing age. But how far does this trend go towards higher life expectancy? With the help of statistical methods, researchers have now been able to calculate that the previous age record of 122 years will be broken with almost one hundred percent probability in the 21st century. According to their calculations, it would also be possible to conceive 130 years of age, on the other hand, 135 or 140, highly unlikely.
How old can a person get? This question is scientifically controversial. While some assume a theoretically unlimited lifespan, others believe that there is a maximum age that can be reached. Nearly half a million people in the world are now over 100 years old, and their numbers have been increasing for decades. There are much fewer people than “centenarians”, that is, they live to be 110 years of age or older. France’s Jeanne Calment, who died in 1997, holds the previous age record of 122 years. The oldest living person at the moment is 118-year-old Ken Tanaka from Japan.
The mortality curve is very similar
Statisticians Michael Pierce and Adrian Raftery of the University of Washington have now calculated how likely it is that the previous age record will be broken by 2100, and what the probability is that people will have a significantly longer lifespan. “Understanding longevity is important because it greatly influences government programs, economic policy, and individual planning,” the authors wrote. “Through this work, we determine how likely an individual is to reach different extremes in this century.”
As the basis for their analyzes, they used the International Database on Longevity, which lists people from 13 countries whose age can be demonstrated to be at least 110 years. The researchers combined this information with statistical models, also taking into account future population growth. In addition, it included a statistical peculiarity for very old people: from a certain age, the mortality curve is again flattened.According to observations, from the age of 110, the probability of living in another year is about 50 percent – regardless of whether one is 110, 112 or 114 years old. “This is a very select group of very strong people,” Raftery explains. “You left behind all the different things that life brings with it, like diseases. They die of causes fairly independent of what matters to young people.”
Realistic 130 years
These centenarians are very rare, and their number is currently estimated at only about 300 to 450 people worldwide. As the population grows, the likelihood that there will be more of these people increases – however current lifespan records will be shattered. “Based on our methodology, we have found that the probability of breaking the current lifespan record of 122 years and 164 days in this century is close to 100 percent,” the researchers report. “The probability of a person reaching the age of 126 is very high at about 89 percent, and the probability of a person reaching the age of 130 is still realistic at about 13 percent.” This person, on the other hand, will have a hand age of 135 or 140 years by 2100, according to calculations, although it is possible, it is extremely unlikely.
Pierce and Raftery see their statistical approach as an alternative to traditional attempts to determine the maximum possible human lifespan. While some scientists have argued that there is no upper age limit, others have argued that degeneration of cells leads to a natural limitation of their lifespan – despite the advanced medical possibilities. Pierce and Raftery write: “Our results can be viewed as a way of resolving the apparent conflict between the limitations of human life and the lack of certain limitations on human life.”
Coyle: Michael Pearce and Adrian Raftery (University of Washington), Demographic Research, doi: 10.4054/dimeris.2021.44.52