Nasal foreign bodies are managed as an emergency for the risk of aspiration, yet it is not clear what proportion of bronchial foreign bodies actually originate in the nose. The aim of this study was to identify the origin of bronchial foreign bodies and estimate the risk of a nasal foreign body becoming impacted in the bronchial tree. We present a retrospective study of suspected bronchial foreign body cases at Addenbrooke's Hospital in Cambridge, UK, who underwent a bronchoscopy between 2002 and 2007. We further compare our experience with a literature review on bronchial and nasal foreign bodies to highlight important differences between these distinct clinical problems. Our experience shows that all cases of proven foreign body at bronchoscopy had ingested the foreign body orally. We could find only one case of a nasal foreign body in the literature that had been ingested during its removal, but no cases specifically entering the tracheo-bronchial tree. We therefore conclude that bronchial foreign bodies have their origin almost invariably in the mouth and the risk of a nasal foreign body entering the bronchial tree is negligible (<0.06%).