The death of the world’s oldest person at age 118 has reignited a debate that has divided scientists for centuries: Is there a limit to the lifespan of a healthy person?
After the death of French nun Lucille Randon last week, 115-year-old Spanish grandmother Maria Branyas Moreira has been named the oldest living person, according to Guinness World Records.
And in the 18th century, the French naturalist Georges-Louis Leclerc, known as the Comte de Buffon, theorized that anyone who did not have an accident or illness could live up to 100 years.
In 1995, French Jeanne Calment surpassed these estimates to celebrate her 120th birthday and died two years later at the age of 122. At least according to recorded data, she was the oldest person alive.
According to the United Nations, there will be an estimated 593,000 people aged 100 and over in 2021, surpassing the 353,000 recorded in the previous decade.
The number of centenarians is expected to more than double in the next decade, according to the Statista data agency.
Is 115 the normal limit?
Scientists have different views on how old we can get, with some arguing that the longevity of our species is limited by strict biological constraints.
In 2016, geneticists wrote in the journal Nature that there had been no improvement in human longevity since the late 1990s.
By analyzing global demographic data, they found that the maximum human lifespan has fallen since Calment’s death, even though there are more elderly people in the world.
“They concluded that there are natural limits to human life span, and that longevity is limited to around 115 years,” French demographer Jean-Marie Robin told AFP.
“This hypothesis, however, is slightly contested by many demographers,” added Rubin, who has a century-old specialization at the medical research institute INSERM.
Research conducted in 2018 revealed that the death rate increases with age, but slows down after age 85.
The death rate at age 107 is increasing at 50-60% every year, according to the study.
“According to this theory, if there are 12 people who reach the age of 110, six go to 111, three to 112, and so on,” says Rubin.
But the older the centenarians are, the better chance a few will live to beat the longevity record.
If there are 100 elderly people, “50 will live to 111, 25 will live to 112,” says Rubin.
But Rubin and his team will release research this year showing that the death rate continues to rise beyond age 105, narrowing the window.
“Currently there is no definitive answer,” said France Mesli, a demographer from the French Institute for Demographic Studies (INED).
“Of course, some medical discoveries in the future may increase everything we know about death,” he said.
Eric Boulanger, a French doctor specializing in the elderly, said that “genetic manipulation” could allow some people to live 140 or even 150 years.
Source: Medical Express
Source: Arabic RT
