There's a good New Yorker piece on this: https://www.newyorker.com/magazine/2020/02/17/was-jeanne-calment-the-oldest-person-who-ever-lived-or-a-fraud https://ww

There's a good New Yorker piece on this: https://www.newyorker.com/magazine/2020/02/17/was-jeanne-calment-the-oldest-person-who-ever-lived-or-a-fraud https://www.newyorker.com/magazine/2020/02/17/was-jeanne-cal... TL/DR: on balance the author concludes that it's easier to believe that she was genuine, all in all.