RIO DE JANEIRO: A Brazilian woman has elbowed out an elderly American as the oldest person in the world, the Guinness organization said Wednesday. Maria Gomes Valentim, 114, was certified as the world's oldest person, edging past US woman Besse Cooper, who is 48 days younger. Valentim, who has been a widow since 1946 and is confined to a wheelchair, is from Minas Gerais state. She credited a healthy diet with giving her a long life.