LongeviQuest recently reviewed the case of Mr. Denzō Ishizaki of Japan – a previously validated supercentenarian who held the titles of the world’s oldest living man and Japan’s oldest man ever at the time of his passing in 1999, at the age of 112.

His age had previously been validated by the Gerontology Research Group. However, upon reviewing the documentation, the Global Validation Commission concluded that his validated date of birth was incorrect. For about two decades, since GRG’s validation, it was believed that Ishizaki was born on October 20, 1886. The evidence located by two LongeviQuest Japan researchers, Ryohei Asano and Yumi Yamamoto, shows that Ishizaki was older than what was previously believed.

Based on information from the family register and the National Directory of Senior Citizens, the Commission concluded that his actual birthdate was October 2, 1886, meaning he was 18 days older. Therefore, his final age was not 112 years, 191 days, but 112 years, 209 days.

At the time of his passing, he was the oldest living man and person in Japan, the world’s oldest living man, and the oldest Japanese man ever. He was never recognized for these titles, as the claimed 120-year-old Shigechiyo Izumi was still believed to have been older, and it was not until 2011 that his validation was withdrawn.