Bring up the Bodies was named the 2012 Costa book of the year last night in London, making its author Hilary Mantel the first novelist to win both the Man Booker (twice) and Costa prizes.

"One book simply stood head and shoulders, more than head and shoulders … on stilts, above the rest," declared the chair of nine judges, Dame Jenni Murray. "We had a really good discussion, like being at a high-powered book club, and I said, 'OK, let's have a vote on Bring up the Bodies' and every hand went up.

"I'd like to tell you there was blood on the carpet, there wasn't. There was absolute unanimity," Murray continued. "Everybody knew there was just one book we know has had lots of prizes but we couldn't allow the number of times it has been lauded to affect our decision."

The Costa Prize differs from the Man Booker Prize in that it mixes genres in the nominations. There were five category winners bidding to win the £30,000 main prize - poetry was contending with biography, first novel was aiming to beat children's book and novel.

Bring up the Bodies hardly needs such boosts, and the novel has sold 240,000 hardback copies already, significantly ahead of the other four contenders, which have yet to sell more than 30,000 together.

"I was writing for many, many years and I was not among the prizes at all or I was a perpetual runner-up, and things have changed in a big way, " declared Ms Mantel. "I feel my luck has changed – of course that's not true, what's changed is that I'm working on possibly the project that's played to my strengths and a project that came along just when I was ready for it."

Foreign translations and TV and stage versions have only swelled the whole Mantel/Thomas Cromwell phenomenon into widespread currency. "I should have known that Thomas Cromwell was bigger than I was, " sais Mantel. "It is as if he has been revivified with a driving will to conquer all media and all languages."

Mantel is now working on the third novel in the trilogy, taking the rise of Cromwell until his downfall in 1540.

After the author won her first Booker prize with Wolf Hall she promised to spend the money on sex, drugs and rock 'n' roll. The second time she won the prize quipped the money would be spent on rehab. For the Costa she declared the money would go to her "pension fund".