Jeanne Calment was indeed the oldest human being
By combining epidemiology, mathematical modelling and historical investigation, researchers in Geneva, Switzerland and France confirm Jeanne Calment鈥檚 exceptional longevity, invalidating the conspiracy theories surrounding her.
Jeanne Calment at the age of 20. 漏 All rights reserved
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Jeanne Calment, who passed away in 1997 at 122 years and 165 days, still is today the human being who had the longest life. This exceptional longevity has been subject to numerous investigations, both during her lifetime and after her death, to confirm this record.听 A Russian team questioned it at the end of 2018, suggesting a family conspiracy to commit insurance fraud, Ms. Calment鈥檚 record is now confirmed. Researchers from the 玉美人传媒 (UNIGE) and the 玉美人传媒 Hospitals of Geneva (HUG) in Switzerland, as well as from the Institut National de la Sant茅 et de la Recherche M茅dicale (INSERM) and the 脡cole Pratique des Hautes 脡tudes (EPHE) in France, provide historical and epidemiological evidence of the longevity of humanity鈥檚 oldest person ever. Their mathematical model also highlights the likely increase in the number of people over 120 years of age. These results can be discovered in the Journal of Gerontology.
More than twenty years after her death, Jeanne Calment is still the human being who lived the longest life. This exceptional longevity is still surprising and is regularly questioned. A few months ago, Nikolay Zak, a young Russian mathematician, assumed, among other things, that it was statistically impossible for a human being to reach the age of 122. He then claimed that Jeanne Calment was in fact her daughter Yvonne, who would not have died of tuberculosis in 1934, but would have fraudulently taken her mother鈥檚 identity. Demographer Jean-Marie Robine, a researcher at INSERM and the Ecole pratique des hautes 茅tudes, had already provided historical evidence of Ms. Calment鈥檚 longevity in 1998 in an article published in Science. He had also met with Ms. Calment several times before her death to confirm her status as humanity鈥檚 oldest person. 鈥淭he Russian team鈥檚 芦conspiracy theory禄 directly challenged my work,鈥� he explains. 鈥淪o, together with my colleagues, we not only ran through the historical and demographic survey from scratch once again, but we also examined in detail the mathematical hypothesis proposed by Nikolay Zak.鈥� To conduct this work, he called on Fran莽ois Herrmann, Professor at UNIGE Faculty of Medicine, senior physician in the HUG geriatrics department and an expert in the epidemiology of elderly people.
A robust mathematical model
Fran莽ois Herrmann explains his approach: 鈥淚s it possible to live to 122 years old? This question summarizes the whole controversy surrounding Jeanne Calment. To find out, we designed a probabilistic model based on solid demographic data.鈥� The researchers reconstructed the complete cohort of all the people born in France in 1875 鈥� Ms. Calment鈥檚 year of birth 鈥� to determine their age at death. They then repeated the exercise for the year 1903, which is the last extinct cohort (there are no longer people alive in France who were born in 1903).听 In order to build a reliable model and limit random fluctuations, extreme values 鈥� age figures for which there were less than 30 deaths 鈥� were then excluded.听 Based on these data, survival probabilities at 100 years, then at 101 years, 102 years, etc. were then calculated. 鈥淲e finally applied these survival probability figures to a virtual population of 100,000 centenarians to determine the maximum extinction age of the cohort. We reach an age between 119 and 123 years. Thus, every 10 million centenarians, a person can reach 123 years of age.鈥� A probability that is certainly small, but that is far from making Ms. Calment a statistical impossibility.
More and more 鈥渟upercentenarians鈥�
At the time of Ms. Calment鈥檚 death, the new humanity鈥檚 oldest person was 鈥渙nly鈥� 112 years old, 10 years younger. 鈥淎 significant gap that made Ms. Calment an anomaly,鈥� says Professor Herrmann. 鈥淪ince then, however, one person has reached 119 years of age, and five others 117 years of age. The gap is narrowing! Ms. Calment was simply a little ahead of her time.鈥�
What is the secret of this longevity? It must have been a mixture of good genetic heritage and luck, as Jean-Marie Robine explains: 鈥淢any of Ms. Calment鈥檚 ancestors lived a particularly long time, as did her brother. In addition, the family was well-off and educated, two socio-economic factors that still predispose to good longevity today.鈥� Unfortunately, Ms. Calment鈥檚 grandson died young and without descendants in a car accident; therefore, it is impossible to assess this family hypothesis.
The article, written by Professors Herrmann and Robine among others, also takes up in detail the history of Ms. Calment鈥檚 life and proves that she, far from family plots and embezzlement, has lived 122 long years. Will others join her soon? In view of the ever-increasing number of centenarians, it is most likely.