Matthew McConaughey isn't the only one wasting away for his Dallas Buyers' Club role.

Jared Leto, who signed on to the flick just a few weeks ago, has already undergone a dramatic transformation for his part in the drama -- debuting a newly scary-skinny bod and shaving off his eyebrows -- in order to play a transsexual woman with AIDS in 1980s Texas.

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Despite his intense weight-loss process -- Leto told Vulture at the IFP Gotham Awards in NYC Tuesday he's been fasting for the last month or so -- the actor says he's more concerned with mastering his character's grooming techniques, like waxing his body (and facial) hair.

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"Your body goes through weird stages [when fasting]," he shared. "Sometimes it's hard to hold on to water. But for me, it's not about the most weight I can lose, it's more to represent the character. I'm focused on what it means to be a transsexual woman."

As hungry as he might be (he admitted to feeling lightheaded), Leto, 40, is also doing his best to look on the bright side.

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"Historically, people have [fasted] for pursuit of self, to achieve a meditative state, so I'm hoping for that, and not the other things," he said, laughing. "It's not necessarily a bad thing."

This article originally appeared on Jared Leto Opens Up About Dallas Buyers' Club Weight Loss, Shaving His Eyebrows