Japan has about 100,000 people who have lived for a century or more — the most in the world, and more per capita than in any other country. But for some people, reaching 100 is just another milestone in a full life. We met five remarkable centenarians who credited their longevity to eating well, Japan’s affordable health care, exercise and family support. But for these five, there is also something else: their work. When Tomeyo Ono plopped onto a cushion to begin her performance, there was total silence. Then, from somewhere deep in her petite body, she started to recite the folk tale of a bull and a baby bear. As she spoke, she gestured wildly with her hands, the audience hanging on every word. At the end, the room filled with applause. With a repertoire of 50 stories, Ms. Ono is a teller of minwa, or folk tales, a career she took up for fun after turning 70. Now 101, she is the oldest, and loudest, member of a storytelling collective. After the 2011 tsunami washed away her home in Fukushima, she vowed to incorporate the experiences of its survivors into her work. “I’m living to tell my stories,” Ms. Ono said, tears rolling down her cheeks. She said she was terrified by the idea of folk tales, or memories of the tsunami, being lost. Every day, she writes in her journal and eats natto. Occasionally, she dozes off while reading the newspaper as her daughter-in-law tidies up around her. “I get special treatment because I’m the oldest,” she chuckled.