Extreme body transformations are increasingly popular in Hollywood, whether you're Hugh Jackman turning into a mountain of bone and gristle to play Wolverine or Matthew McConaughey wasting away in Dallas Buyers Club.
But neither stuffing your face nor starving are guarantees of box-office success, as these actors learned...
1. Christian Bale – The Machinist
Bale famously cemented his serious-actor chops by dropping a reported 63lbs to play a psychologically disturbed insomniac who has lost a scary amount of weight. We've seen the pictures – but how many of us have seen the movie?
2. 50 Cent – All Things Fall Apart
Curtis '50 Cent' Jackson also lost a ton of weight, this time to play an American football player diagnosed with cancer. Comparisons to The Room are probably not what Fiddy was looking for, but that's what he got.
3. Jared Leto – Chapter 27
Of course, Jared Leto has had his share of success for dramatic body transformations, winning an Oscar after shedding his muscles for Dallas Buyers Club. But six years earlier, his decision to pile on the pounds to play John Lennon's murderer Mark David Chapman resulted in mega flop Chapter 27 – and a nasty case of gout for Leto.
4. Colin Farrell – Triage
Back in 2007, when Colin Farrell had yet to fully shed his unsuccessful leading-man disguise to reveal the very decent character actor beneath, he had a go at gritty drama in Triage. He slimmed down 44lbs by eating two tins of tuna a day to play a psychologically troubled war photojournalist. And no, we'd never heard of it either.
He later acknowledged that it was neither "healthy" nor "advisable".
5. Chris Hemsworth – In the Heart of the Sea
In our minds, Chris Hemsworth is firmly lodged in the pantheon of superhero stars called Chris with massive muscles. But for Ron Howard's whaling movie he shed his Thor physique (and 33lbs) for the emaciated appearance of a castaway. Too bad the movie sank without trace.
At one point he and his co-stars were eating a single boiled egg, a stick of celery and a couple of crackers a day. "Wouldn't recommend it," he said.
6. Domhnall Gleeson – Unbroken
Angelina Jolie's triumph-over-trauma story of Olympian and WW2 prison-camp survivor Louie Zamperini was once touted as potential Oscar material, but sadly it didn't catch fire at the box office. Something the cast probably regretted, given what they went through to make it. Domhnall Gleeson said: "My contact lenses stopped fitting my eyes, because I was so dehydrated and had lost so much weight."
7. Matt Damon – The Informant!
Steven Soderbergh's 'biographical-comedy-crime film' The Informant! was a bit of a non-starter at the box office, despite Matt Damon adding 30lbs to his normally trim figure. It's not all bad though – Damon described eating everything in sight as "probably the funnest time [he's] had working".
Certainly more fun than he had making Courage Under Fire in 1995, when he lost something like 60lbs eating just chicken and running 13 miles a day to play a heroin-addicted ex-serviceman.
