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Home / Science / Is there a limit to the aging of humans? A new study suggests that the death rate does not rise at the age of 105 years

Is there a limit to the aging of humans? A new study suggests that the death rate does not rise at the age of 105 years



Jeanne Louise Calment lived 122 years and 164 days, the oldest detectable age ever. Her interviews revealed a portrait of the centenarian in high spirits: "I've only had one crease and I'm sitting on it," she told reporters when she turned 110.

Calment died in 1997 in Arles, France, where she spent much of her impressively long life. No one has lived to exact records over 120 years.

Whether there is a limit to the human lifespan is an age-old question. An actuary named Benjamin Gompertz suggested in 1825 that the mortality rate increases exponentially with age. Under the so-called Gompertz Act, the probability of dying every eight years is doubled. This seems to be the rule for people between the ages of 30 and 80 years.

But the researchers do not agree on what happens to mortality rates very late in life. A new study, published Thursday in the journal Science, reveals that the Grim Reaper suddenly goes off the gas

"The goal was to create a controversy over whether human mortality would be the same as mortality in many other species has to solve, "said study author Kenneth Wachter, emeritus professor of demographics and statistics at the University of California at Berkeley. Mortality rates were found to decrease in laboratory animals, such as Mediterranean fruit flies and nematode worms. "We think we fixed it," he said.

Accelerate mortality rates to age 80, then slow and then plateau between ages 105 to 110, the authors of the study concluded. The Gompertz law ends in a flat line in this view.

To be perfectly clear, we're talking about accelerating mortality rates, not chances themselves. They're still not good. Only 2 out of 100,000 women live to 110; For men, the chances of becoming a supercutenarian are 2 to 1,000,000. At the age of 105, according to the new study, the chances of surviving until your 106th birthday are 50 percent in the stadium. It's another 50-50 coin toss 107 then 108, 109 and 110.

Under the direction of Elisabetta Barbi at the University of La Sapienza in Rome and experts from the Italian National Institute of Statistics, all were born in Italy between 1896 and 1910, who lived 105 years or older. The data included 3,836 individuals, of which 3,373 were women and 463 were men. The National Italian Register, which requires annual updates from citizens, provides more accurate information than US Social Security data. "Italy probably has the best data we have," Wachter said.

Holger Rootzen, a statistician from Chalmers University of Technology, Sweden, described the study as "very careful and good analysis" between 105 and

using similar longevity data from Japan and Western countries Planck Institute for Demographic Research, Rozenzen, in a December study published in Extreme magazine, rejected the idea of ​​a hard limit to human life. He predicted that in the next quarter century, someone would be 128 years old.

Two years ago, researchers at the Albert Einstein College of Medicine in Nature based on data from 40 countries argued for a maximum limit at about 115, the Washington Post reported. In her view, Calment's lifetime was a stroke of luck.

Brandon Milholland, who worked as a PhD student on the Nature study, said it was "highly unlikely" that the mortality curves weaken so suddenly and flattened.

"There are more than these two options," said Milholland on Wednesday. In a statement, his co-author Jan Vijg, a geneticist at the Albert Einstein College of Medicine, called the choice between a sharp plateau or Gompertz's law a "false dichotomy."

"Your error bars are big," said Milholland This leaves room for steeper corners through the Italian data. He agreed that the Gompertz Act should end, as mortality rates could not exceed 100 percent. But this study has not convinced him that the mortality rate stops at about 50 percent.

Rozenzen contested the conclusions of the Nature paper, which estimated a lifetime limit, and said the authors made a statistical mistake: Yes, the chances of living beyond 115 are low, but that does not mean that one Boundary exists, he said. He used the example of throwing darts on a dartboard. In 10 throws, you will not get a Bull's Eye. Throw thousands of darts at a dartboard and maybe you will do that.

"You simply do not understand this problem if you make more attempts" – more arrows on the dartboard or more people who are very old – "Then the record will be higher," said Routzen.

The numbers of the very old grow. In Italy, for example, four people born in 1896 lived to age 105 or older. More than 600 people born in 1910 lived so long. Between 1896 and 1910, infant mortality improved in Italy, Wachter said. In later decades, the care of 80- and 90-year-olds also improved as more people were added to the centenarians.

"Understanding the Interactions between Our Genomic Heritage and All These Other Well-Investigated Practical Factors Like nutrition and behavior, we will understand why people are able to make and advance this progress in the 1980s and 1990s ", he said.

So far, the oldest among us have come from all walks of life. "The lifestyle recommendations – you train, you eat this or that – these are quite effective at a young age, but seem to play no role in older years," said Routzen.

Calment said she smoked two cigarettes a day until she was 119 years old and only then kicked the habit because she did not see well enough to light.


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