Guinness World Records oldest living man, who said the secret to a long life was smiling, has died at 112. Chitetsu Watanabe of Niigata, Japan died Sunday, Guinness World Records and the funeral home handling his services confirmed Tuesday. On Feb. 12, Guinness World Records presented him a certificate as the world's oldest living man at age of 112 years, 344 days. Watanabe said the secret to a long life ...