Christian Bale lived on just a can of tuna and an apple a day and lost 60 lbs. while filming The Machinist in 2004. He claims that cutting down his food intake made him more relaxed than he has ever been before or since.
The 36-year-old star said: "I was the calmest mentally that I've ever been in my life. You just go beyond any bodily needs. Your energy gets to such a low point that it all just becomes mental. You felt like some sort of guru that could go sit on top of a mountain."
Despite finding inner peace from his diet, Christian—who has a notorious temper on film sets—won't ever repeat the experience.
He said: "Mentally, it does wonders, but I would never sacrifice the joys, the ups and the downs, the rollercoaster of life for that calmness. I'd rather be getting in there, getting involved and having it a bit more raw than that."
The actor plays Dicky Eklund, the half-brother and trainer of Boston's 'Irish' Mickey Ward (Mark Wahlberg) in the new biopic The Fighter.
But he relied on make-up rather than weight loss to go from playing a drug addict to a reformed boxing coach during the shoot.
He explained to MTV News: "I had to take it right to the cusp so that I could go with make-up from being the crackhead to also with the help of make-up being the cleaned up Dicky when he got out of jail. I had to do it without the luxury of losing huge amounts of weight in between because we shot the movie so quickly."