Matthew McConaughey lost 30 pounds. Hugh Jackman lost at least 20. Anne Hathaway lost 25.
The Hollywood celebs cut weight for roles ranging from an AIDS patient to a destitute prostitute through a simple (but extreme) method: total or near-fasting.
"It takes a while for your body to understand that it has to feed off itself, and that you're not going to give it something else from the outside," McConaughey told ABC. "I should not look healthy by the time I'm doing this."
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Hathaway, who lost 15 of the 25 pounds in a two-week period by subsisting on two squares of dried oatmeal paste a day, said she experienced sleeplessness from hunger.
"I had to be obsessive about it -- the idea was to look near death," she told Vogue. "Looking back on the whole experience -- and I don't judge it in any way -- it was definitely a little nuts."
The side effects aren't surprising, said registered dietitian Joy Dubost, a spokeperson for the Academy of Nutrition and Dietetics.
"You're putting the body under tremendous stress," she said.
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