Sebastian Stan was fasting "for 16 to 18 hours a day" to play Tommy Lee.
Sebastian Stan embarked on a gruelling weight-loss journey
The 39-year-old actor went to extreme lengths to lose weight for his role in the TV drama series 'Pam and Tommy'.
He explained: "I was trying to lose weight and I still felt I didn't lose enough weight. And people were telling me I was crazy and going, 'You have body dysmorphia now' - which I always did anyway."
Sebastian stopped exercising for months in order to transform his physique.
But Sebastian was initially unsatisfied with the results of his weight-loss regime - and he then decided to take the situation a step further.
He explained to Entertainment Weekly: "I was just running and trying to get 20,000 steps a day, and then I was fasting for 16 to 18 hours a day. And that definitely does something, especially if you're [driving] in traffic. But I'm proud of the whole thing."
Sebastian - who stars in the show alongside Lily James - doesn't worry about the long-term impact of his weight-loss efforts.
He said: "Anybody that even has a healthy physique to some extent has body dysmorphia. Because once you're going into a peak, the best look possible, which by the way, I don't care what they say, unless there's like, magic formulas out there - which there are but some of us are not in that pocket - your body can only be at peak 100 percent for like maybe a week or something.
"At least, how I've experienced it; and I mean diet and exercise and tanning and water and lighting and everything. And then you spend the rest of the time going, 'I'm not what I used to be.' But it's just all in the head."
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