Can people grow horns (and other bizarre questions doctors are asked)

Can people grow horns (and other bizarre questions doctors are asked) | UPDATED: 21:01 GMT, 29 September 2012 Have you ever wondered if chocolate really does give you spots, or just how much of our brains we actually use In an extract from his new book of weird and wonderful health trivia, writer DAVID HAVILAND reveals the answers to these questions, and other bizarre facts from the world of medical science.