Amanda Seyfried can't stop thinking about her weight.
"I clearly like being fit, but it's not thin without a hell of a lot of work - I run and I exercise a lot and then I eat," she tells Stylist UK.
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"I'm in my mid-20s and I know how to look after my body on my own. I'm not going to deny that I don't think about it every day, it's always on my mind," she continues.
The actress, 24, told the April issue of Esquire that she put herself on a restrictive raw diet in which she only ate spinach.
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"The week of that interview I was on a raw food cleanse, which I do occasionally," she admits.
Normally, "if I have to diet, it's salad with protein, salmon and broccoli, no dessert," she says. "But what kind of life is that? So I work out a lot and I'm just pretty moderate about what I eat."
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It's her job, she says, to be body-obsessed.
"I have to stay in shape because I'm an actress," Seyfried explains. "It's f--ked up and it's twisted, but I wouldn't get the roles otherwise. If I'd been bigger, I don't think they would have cast me for Mamma Mia!"