Joaquin Phoenix Says Losing 52 Lbs. for Joker Made Him Develop a ‘Disorder’

Joaquin Phoenix took his weight loss to the extreme in preparation for his new movie, Joker.

The actor, 44, agreed to lose 52 lbs. at the urging of director Todd Phillips, who thought his character, Arthur Fleck, should be “real thin.” Phoenix lost the weight carefully, under the guidance of a doctor, but the strict calorie deprivation he endured affected his eating habits well after he hit his goal.

“Once you reach the target weight, everything changes,” he told the Associated Press. “Like so much of what’s difficult is waking up every day and being obsessed over like 0.3 pounds. Right? And you really develop like a disorder. I mean, it’s wild.”

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Though he struggled mentally with the weight loss, Phoenix found that he physically felt much better than he expected.

“I think the interesting thing for me is what I had expected and anticipated with the weight loss was these feelings of dissatisfaction, hunger, a certain kind of vulnerability and a weakness,” he said. “But what I didn’t anticipate was this feeling of kind of fluidity that I felt physically.”

“I felt like I could move my body in ways that I hadn’t been able to before,” he continued. “And I think that really lent itself to some of the physical movement that started to emerge as an important part of the character.”

Phoenix previously said that he had wanted to gain — not lose — weight for the role, because he was wary of losing such a large amount of weight in a short time span. Phillips convinced him otherwise, and Phoenix said it did have an impact on his mental state.

“As it turns out, that impacts your psychology, and you really start to go mad when you lose that much weight in that amount of time,” he said in August.

Joker opens in theaters on Friday.