“He needs a wheelchair to move but he is in good condition,” said Ms Yuko Nonaka, his granddaughter.
“He loves eating any kinds of sweets – Japanese or western style,” she told AFP.
“He reads newspapers everyday and often soaks in the hot springs.”
He has seven brothers and one sister who live nearby in the town of Ashoro on Hokkaido.
He married Hatsuno in 1931 and the couple had five children, according to Guinness World Records.
Mr Nonaka has officially taken the title after Francisco Nunez Olivera from Spain died in February aged 113, the organisation said.
Guinness World Records is currently investigating possible contenders for the title of oldest living person as no one has been recognised since Violet Brown from Jamaica died in July 2017, aged 117.
The greatest authenticated age for any human is 122 years, 164 days by Jeanne Louise Calment of France, who died in 1997.
Japan, known for the longevity of its people, has been home to several oldest title holders, including Jiroemon Kimura, who died in June 2013 at the age of 116.
There are around 68,000 people aged 100 or older in the country, the government said last year.