Izumi's claimed birth date of 29 June 1865 was accepted by Guinness World Records, which recognized him as the oldest verified man ever, but this was eventually withdrawn in 2010; in the 2012 edition of the Guinness World Records book, Christian Mortensen was named the "oldest verified man ever" and Izumi was not mentioned.

[1] Guinness World Records found a document attesting that he was 24 years old in 1889 when he was exempted from military service to deal with sugar cane fields.

[citation needed] Izumi drank brown sugar shōchū (a Japanese alcoholic beverage often distilled from barley or rice), and took up smoking at age 70.

[5][6] The 2011 Guinness World Records book states that the birth certificate submitted as evidence might have actually belonged to a deceased brother, and the family may have re-used "Shigechiyo" as a necronym.

[7] With the closing of the Guinness World Record Museum in Niagara Falls, Ontario, in September 2020, the display and fibreglass statue of Izumi was sold for $850 on February 12th 2021 and now resides in a private collection in Canada.