This article is taken from the monthly Sciences et Avenir – La Recherche n°904, dated June 2022.
Twenty-one thousand. This is the number of centenarians in France, according to the last census of the National Institute of Statistics and Economic Studies (Insee) in 2016, i.e. 20 times more than in 1970 (1100). By centenarian, we mean someone who has blown out his 100 candles and sometimes even more, such as Jeanne Calment who died at 122 years and 5 months (read S. and A. #864) or the French sister André, born Lucile Randon, recently named dean of humanity with 118 years. In 2070, still according to INSEE projections, they will be more than half a million (540,000). But if France is in Europe the country with the most centenarians, unfortunately not all of them are in good health. It is therefore elsewhere that you have to go to find those who have kept a good footing, a good eye. Head to Japan, the United States, Costa Rica, Greece and Italy, all so-called healthy longevity zones, most of which have been identified by the review. National Geographic in 2011 with the Blue Zones project. But would these places on Earth really hold an elixir of youth? The question obviously has long animated all those in search of the secret of the longevity of centenarians.
“Here, we just forget to die “, confided to Dan Buettner, journalist of the National Geographic, a 101-year-old resident of the Greek island of Ikaria. The explanation can seduce but it has its limits. A more scientific approach, that of the University of Southern Denmark and conducted on more than 20,000 twins, compared the differences in longevity between identical and false twins. “This work has shown that identical twins die with a difference in lifespan of three years, while the average between identical twins is six years. “, recounts in his latest book (cure old age, HumenSciences, 2022) Jean-Marc Lemaitre, researcher in cell biology and specialist in aging. Who continues: “This work has made it possible to estimate that the share of genes in longevity is 25%, the remaining 75% being attributable to environmental factors and “lifestyle”. ” This last somewhat “catch-all” expression in fact accounts for the way in which individuals eat, but also drink, breathe, move, work, in short, live. Also, concentrating solely on the content of the plates of centenarians is necessarily simplistic.Moreover, exclusively nutritional analysis has always disappointed.
Food intake largely from plants
The few local specialties consumed by the inhabitants of the “blue zones” – Japanese seaweed, Greek sheep’s milk, rosemary and Italian cheese, corn tortillas… – obviously do not contain any magic “anti-ageing” molecule.