Sydney Sweeney Opens Up About Rapid 30-Pound Weight Loss for Character

Sydney Sweeney says her body went through major changes while preparing for and recovering from her role in the boxing film Christy.

She spoke with PEOPLE about the process and explained how she first had to gain more than 30 pounds and then quickly return to her usual size once filming ended.

The actress said the weight gain took months and required her to switch to a heavy eating routine along with intense strength training. She explained to PEOPLE that she was eating large amounts every day to match the physical look of boxer Christy Martin. She said, “I was eating so much food. Like, everything you could possibly imagine,” and added that she drank protein shakes constantly and used creatine, which she said made her feel bloated.

When filming wrapped, Sweeney had only seven weeks before she needed to appear in two new projects: The Housemaid and the new season of Euphoria. She told the outlet that she had to commit fully to the weight loss process. “I had to be really strict with myself,” she said while describing how she shifted from gaining muscle to letting that muscle drop.

Sydney Sweeney says she only had seven weeks to drop the 35 pounds she gained to play Christy, because right after she was jumping into 'The Housemaid' and 'Euphoria'. She says the first part went fast, but those last 10 pounds were rough, she had to get super strict. pic.twitter.com/ZmNG3DgSwI

— Sydney Sweeney Daily (@sweeneydailyx) December 9, 2025

She explained that once she stopped the heavy training and cut out the protein shakes, the muscle disappeared quickly. “When you stop working out and taking all your protein shakes, you lose muscle super fast,” she said. “It’s the first thing to go before fat. So, that, I dropped within two weeks.” After that, she focused on eating clean and doing a lot of cardio to lose the rest.

Although she says this transformation pushed her more than usual, she also said her body responds quickly. “I’ve been a very active person my entire life,” she shared. She said her metabolism helps her with both gaining and losing weight when needed, though she hinted she may not take on such extreme changes again.

The movie Christy is now in theaters, while The Housemaid, where she stars alongside Amanda Seyfried, is set to premiere on December 19.

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