Is there an age limit at which a healthy person can live?
The death of the world’s oldest person at the age of 118 has revived a debate that has divided scientists for centuries: Is there a limit to how long a healthy person can live?
Following the death of French nun Lucille Randon last week, 115-year-old Spaniard Maria Branas Moreira has been named the oldest person alive, according to the Guinness Book of World Records.
And in the eighteenth century, the French naturalist Georges-Louis Leclerc, known as the Comte de Buffon, suggested that someone who did not suffer from an accident or illness could theoretically live a maximum of 100 years.
In 1995, Frenchwoman Jeanne Calment celebrated her 120th birthday by surpassing those estimates, and two years later she died at the age of 122. She is still the oldest person to have ever lived, at least according to recorded data.
According to the United Nations, there were 593,000 people aged 100 and over in 2021, up from the 353,000 registered a decade earlier.
According to Statista, the number of centenarians is expected to more than double over the next decade.
The normal limit is 115 years?
Scientists disagree about how old we can live, with some arguing that our species’ lifespan is limited by severe biological limits.
In 2016, geneticists wrote in the journal Nature that there has been no increase in human lifespan since the late 1990s.
Analyzing global demographic data, they found that maximum human life expectancy has declined since Calment’s death, even though there are more older people in the world.
“They came to the conclusion that human lifespan has natural limits, and that lifespan is limited to about 115 years,” French demographer Jean-Marie Robin told AFP.
“But this hypothesis is partly disputed by many demographers,” added Rubin, who specializes in centenarians at INSERM, an institute for medical research.
A 2018 study found that while the death rate increases with age, it slows down after age 85.
The study showed that at the age of 107, mortality peaks at 50-60% every year.
“According to this theory, if there are 12 people who have reached the age of 110, six will live to be 111, three will live to be 112, and so on,” Rubin explained.
But the older the centenarians, the more likely it is that some of them will live to record longevity.
Rubin said that if there were 100 elderly people, “50 would live to be 111 and 25 would live to be 112.”
However, Rubin and his team are due to publish a study this year that will show that the death rate continues to rise after age 105, narrowing the window.
“At the moment there is no definitive answer,” said France Mesli, a demographer at the French Institute for Demographic Studies (INED).
“Of course, some future medical discoveries may soon overturn everything we know about death,” she said.
Eric Boulanger, a French doctor who specializes in the elderly, said “genetic manipulation” could allow some people to live to 140 or even 150 years.
Source: Medical Express