Jiroemon Kimura, the world's oldest living person at 116 years, is now also the last man on earth who was born in the 19th century, reports The Sydney Morning Herald. The supercentenarian was born on April 19, 1897, in the 30th year of Japan's Meiji period. He has lived through the reigns of four emperors and 61 prime ministers, has seen two world wars, and has experienced the inventions of everything from the airplane to the cell phone. He worked for 45 years for the Japanese post office, and retired in 1962 at the age of 65, the Herald says. Kimura currently lives in the Kyoto Prefecture with the widows of his oldest son and grandson, and says his longevity is due mostly to his habit of eating small portions of food, the paper adds.
Kimura was previously joined in the men-born-in-the-19th-century club by 113-year-old Emmanuel Sisnett of Barbados, who died last week, according to the Herald. It's estimated that there are somewhere between 200 and 300 supercentenarians - people aged over 110 years - living in the world today, but only a handful have the birth records to prove it. And of all those people, only Kimura and a Japanese woman named Misao Okawa are over 115, the Herald says.
Kimura's longevity may be due to his genes, along with his diet, says ABC News. "People who live to that age are incredibly heterogeneous, as if they have some key genetic features in common that get them to an incredibly old age," Tom Perls, from Boston University Medical Center, told ABC.
Perls, the director of Boston University's New England Centenarian Study, said his studies have shown that 90 percent of people who live these extremely long lives are women, likely because having two X chromosomes protects against disease to some degree. "If one chromosome has some less-than-desirable aging or disease genetic variance, women seem to have the ability to choose a variant on the other chromosome that is more conducive to survival," he told ABC.
Perls' research has also shown that women who conceive children naturally and carry a baby to full term after age 40 are four times as likely to see their 100th birthdays, ABC adds.
And while approximately 20 percent of people over the age of 103 either smoke, drink, or eat poorly, Perls said it's rare for smokers to make it past the 100-year mark. The oldest woman who ever lived - 122-year-old Frenchwoman Jeanne Calment, who died in 1997 - was a life-long smoker, ABC says. But Perls thinks she might have lived even longer had she quit.