Cillian Murphy gave up being vegetarian because he didn't want to be a "skinny Irish fella".
The 'Peaky Blinders' star decided against eating meat around 15 years ago because he was "worried about getting mad cow disease" but has now decided to go back to eating meat so he can bulk up.
He said: "I was vegetarian for about 15 years. But it was never a moral decision. It was more that I was worried about getting mad cow disease.
"For the first series of 'Peaky Blinders', they were anxious that I shouldn't look like a skinny Irish fella, and my trainer recommended meat."
Asked what was his first meat meal, he added: "Actually, it was a venison steak ... A few cocktails had been had before dinner. When the waiter asked if I'd like the fish or the venison, I hesitated and he said, 'Have the venison.' He was right. It was extraordinary. They reared their own deer on the property."
And the 40-year-old actor hopes he won't "grow old disgracefully".
He added: "Most middle-aged men are engaged in some form of self-improvement, like yoga or giving up drinking. You don't want to grow old disgracefully if you can help it."
And Cillian's career could have been very different as he revealed he and his brother were offered a five-album record deal as a boy.
He told Mr Porter magazine: "My brother was still only 16, so my parents wouldn't allow him to sign his life away. And we didn't want to do it without him.
"Anyway, the deal was terrible. It was like, 'Come to London and live in digs somewhere on 50 quid a week, and we'll own all of your music.' So that was our peak, and then it fizzled out."
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