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Throughout our lives, we are becoming aware of a fact that until recently had no answer: the older we get, the closer we are to the end. However, a new and controversial research suggests that there is really no limit to human life.
Jeanne Louise Calment lived 122 years and 164 days, the oldest verified age of anyone ever seen. Calment died in 1997 in Arles, France, where he spent much of his life impressive and extensive. No one (more) has lived more than 120 years.
Perhaps this is the reason why there is a consensus among researchers to accept the so-called Gompertz mortality model, a proposal that has remained largely untouched. the first time almost 200 years ago.
The idea was born in 1825, when the British mathematician Benjamin Gompertz noticed a strange peculiarity of human aging and mortality. Our risk of dying, he observed, is increasing exponentially as we get older. According to the Gompertz model, the chances of dying double every eight years. This seems to be the rule for people aged 30 to 80 years.
But as Gompertz himself admitted, there is simply not enough data to show that this trend is valid for older people. Over the last 10 years, they continue to assert the Gompertz model, including a study from last year that showed that supercensemen, people who live 110 years or older, still experience rates of accelerated mortality over time.
In recent years, some have begun to question the Gompertzian paradigm, suggesting that mortality plateaus, in which mortality rates decrease or even stop, exist for both humans and humans. animals. In fact, there is now a lively debate among aging experts as to whether mortality rates continue to accelerate and / or exponentially at an extreme age, or if they end up stagnating.
Graph showing probabilities of death (danger) by age (years), with the plateau (represented in orange) after 105 years, so we come to the publication launched a few hours ago in Science. According to the study's author Kenneth Wachter, Emeritus Professor of Demography and Statistics at the University of California at Berkeley:
The goal was to resolve a controversy over the issue of whether human mortality has the same form as mortality in many other species. It has been found that mortality rates are stabilized in laboratory animals, such as Mediterranean fruit flies and nematodes. We believe we have solved it.
The Wachter team tells us that mortality rates accelerate up to 80, slow down, and then stabilize between 105 and 110 years of age. The model of Gompertz, in this view ends with a flat line
In other words, the study speaks of the acceleration of mortality rates, not probabilities themselves. These are still not good. Only 2 in 100,000 women live to 110 years, and for men, the chances of becoming supercentenarians are 2 per million.
the study, at age 105 the chances of surviving your 106th birthday are at 50%. And the same thing happens at 107, and again at 108, 109, and 110.
Another of the authors of the book, Elisabetta Barbi, of the Sapienza University of Rome, brought together experts at the National Institute of Statistics of Italy and he traced locals born between 1896 and 1910 who lived up to 105 years or so. The data included nearly 4,000 people, including 3,373 women and 463 men
. For the statistician Holger Rootzen, of the Technological University of Chalmers, Sweden, the result is a very careful and precise analysis "revealing a mortality plateau between 105 and 110 years.
Using Similar longevity data from Japan and Western countries compiled by the Max Planck Institute for Demographic Research, Rootzen had already rejected the notion of a strict limit for human life in a research published the year The researcher predicted that it would be possible in the next quarter of a century to reach the age of 128.
In 2016, researchers from Albert Einstein College of Medicine competed in Nature, based on longevity data from 40 countries, for a maximum limit of about 115. In your opinion, the life of Calment we were talking about in the beginning was a stroke of chance.
This during, for Brandon Milholland, who also worked on Nature's study, it is "highly unlikely" that mortality curves will stabilize so suddenly. Milholland criticizes both the latest work and Gompertz's law by arguing that there is "more of these two options" and that Gompertz's formulation must stop.
That said, the number of very old people is increasing. In Italy, for example, four people born in 1896 lived up to 105 or more. More than 600 people born in 1910 lived so long " and between 1896 and 1910, infant mortality in Italy decreased ", explains the work of Wachter
When we understand the interactions between our genomic heritage and all these other well-studied practical factors such as nutrition and behavior, we understand why people can advance this 80 and 90 and develop it. Lifestyle recommendations: you do exercise, you eat this or that, they are quite effective at a younger age, but they do not seem to play a role at a later age.
A certain reason must be in the latter. As we said recently, who can become the longest man on the planet has smoked all the time (although he says that it's time to stop) . In fact, Calment herself said that she was smoking two cigars a day until the age of 119, and that's only at that time that she resigned, although she did so because she did not see well enough to light it. [Gizmodo, Science, Washington Post]
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