GoKawiilJiroemon Kimura, who is on record as the world’s oldest man, died at the reported age of a hundred and sixteen, in 2013. His passing spawned a slew of articles about the secret to extreme longevity. (Apparently, it’s small meals.) Kimura is said to have been born in a fishing village in Kyoto Prefecture, Japan, in April or March of 1897. Strangely, he is the only one of his five siblings to have multiple graduation records; he seems to have completed elementary school in 1907, or 1909, or 1911. He supposedly married his wife on three different dates, and at some point he not only adopted his wife’s surname but also changed his first name. (He was born Kinjiro Miyake.) Demographers who attempted to validate his age wrote that their investigation uncovered irregularities and inconsistencies. And yet they concluded that “no critical discordances were discovered.” The word “critical” was doing a lot of work.
Cases such as Kimura’s—and some that inspire even more skepticism—fill the pages of “Morbid: Debunking Modern Longevity Science” (M.I.T. Press), a lively and sometimes conspiratorial new book by the Oxford researcher Saul Justin Newman. Newman won the satirical Ig Nobel Prize, in 2024, for demonstrating that many of the world’s oldest living people may actually be dead. In “Morbid,” he argues that dubious age claims are not isolated—blemishes on the record of, say, Jiroemon Kimura or the famed elder Frenchwoman Jeanne Calment—but, rather, a systemic problem infecting longevity studies. “It is pretty hard to publish a scientific case report about a grandma reaching 88 years old, but if she manages 122 you might even squeeze a book out of it,” Newman writes. An exceptionally long life, in Newman’s telling, is not necessarily a function of good genes, good behaviors, or good luck. It’s evidence of bad record-keeping. The world’s oldest people, he quips, have “birth certificate allergies.”
In accordance with Newman’s theory, many long-lived people are hardly paragons of healthy choices. Christian Mortensen, who held the record for the world’s oldest man before Kimura, smoked for nearly a century. Juan Vicente Pérez—who was born in rural Venezuela, had no official papers until his fifties, and seemingly died at a hundred and fourteen—drank aguardiente every day. The Guinness Book of Records once credited Carrie White, who was given a diagnosis of “post-typhoid psychosis” in her thirties, with being the longest-lived person—until it learned of a clerical error at the psychiatric institution where she spent more than seven decades of her life. “Where are all the athletes?” Newman wonders. “The aerobically svelte, annoyingly pious, scare-you-with-their-abs types? Dead.” According to Newman, the reason that supercentenarians—people who live past a hundred and ten—frequently have unhealthy habits is that they aren’t supercentenarians at all.
In a useful thought experiment, Newman shows how small errors in recorded age can compound to undermine aging research. Suppose that a hundred forty-year-olds fake their ages so that on official documents they’re listed as fifty. (The U.S. Census Bureau has said that millions of Americans misrepresented their age in the most recent census.) In a country that contains a hundred thousand fifty-year-olds, these “young fakers” would account for only 0.1 per cent of the population. No big deal. But because the faux fifty-year-olds are far less likely to die than real fifty-year-olds—after age thirty, our risk of death doubles roughly every eight years—they will come to make up a larger and larger share of their purported age group. At “sixty-six,” they represent 0.4 per cent of their cohort; at “eighty,” three per cent. At “a hundred and five,” they compose virtually the entire population.