Jessica Chastain is an Oscar-nominated actress who has shared the big screen with the likes of George Clooney, Brad Pitt, Viola Davis, Octavia Spencer, Matt Damon, Idris Elba, Kevin Costner, Jennifer Lawrence, and longtime friend Oscar Isaac. She’s also been a formidable presence in both films and series (fans believe Chastain deserves an Emmy for Scenes from a Marriage). Indeed, Chastain appears unstoppable. Unbeknownst to many, however, this actress dealt with a lot in the past. In fact, she once struggled with a condition that made filming difficult, even painful.

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While many stars have had dealt with copious medical conditions, health issues, and straight-up illnesses, a lot of the times fans are blissfully unaware of them. This is because the star wants their fans to focus on their work instead. This must be the case with Jessica Chastain as fans seem to be totally unaware of what she's been through...

She’s Always Been Committed To Staying Fit

Ever since she graduated from Julliard, Chastain has been booking roles left and right. That essentially meant she was always on the go. Despite her busy schedule though, the actress makes sure that she keeps her body in good form. It’s a good way to prep for future action scenes after all.

That said, Chastain has no desire to appear pretentious. “I’m not going to be the girl with the private yoga instructor at my house,” the actress told Rolling Stone in 2011. “I don’t want anyone to think, ‘Oh, she’s famous, she’s different than me.’” Instead, Chastain would make it a point to get up by 5:30 AM to workout.

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For anyone who knows Chastain well, her devotion to staying fit is also understandable. After all, she struggled with a health problem that can make it difficult to travel around and even sit still for makeup and prosthetics.

Jessica Chastain Once Suffered From This Condition

There’s a reason why Chastain isn’t fond of making trips to the makeup chair, especially when she’s expected to be there for hours. “I’ve had some health problems in the past,” the actress revealed during a recent interview with L’Officiel. “I had a pulmonary embolism.”

Pulmonary embolism is a condition that accounts for about a third of cardiovascular-related deaths in the country, according to Penn Medicine. It is characterized by a blockage in one’s lung artery. This is caused by a blood clot, often in the leg, which would break loose and travel to the lungs. When this happens, the blood would suffer from low oxygen levels. Several organs may also become damaged due to a lack of oxygen, including the lungs. One of the most familiar symptoms of pulmonary embolism is swelling in the legs, which Chastain has been determined to avoid while she’s traveling or preparing to film a scene.

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“When I get on an airplane, I always think about how I have to be careful and not get blood clots,” the actress explained. At the same time, preparing to portray the titular character in her new film, The Eyes of Tammy Faye, came with its own set of challenges too since her makeup took hours. “Oh my gosh, it’s like I’m going cross country on a plane every day,” Chastain said. “You have to sit very still; I would wear compression socks on my legs.”

The entire makeup process was also a “pretty anxiety-ridden” experience for the actress. To be able to go through it, Chastain kept herself occupied as much as possible. “What I would do is think: How could I make this into something positive? And I watched Tammy Faye for at least 4 hours every morning,” she recalled. “I watched her, I listened to her, I had an audio file that was just her voice, and when I had to close my eyes for the prosthetics and the makeup and everyone painting me, I would listen and I would repeat after her.”

She’s Made Some Important Health Decisions Over The Years

Fortunately, it seems that Chastain is doing a lot better these days. And that’s because she’s been quite proactive about her health. For instance, she may not like the idea of hiring a personal yoga trainer but she’s a fan of the practice, nonetheless. “Now that I'm in film rehearsals in New York, I do Isaac's workout a couple of times a week, and I also do power yoga online twice a week, and that helps clear my head,” Chastain told Shape. “Working out gives me confidence. It's the sense of being proud of myself. The starting point of exercise is always difficult for me — finding the time and quiet space and feeling that I've got a million other things I need to do.” Reports also indicate that yoga, when done safely, can help prevent blood clots.

Aside from doing yoga, Chastain also made changes to her diet, although it was something that happened by chance. “I found myself going to veganism because a friend of mine had a two week vegan food delivery program she wasn’t going to use so I used it, and immediately I just had more energy than I’ve ever had in my life,” the actress revealed to W Magazine. She did try to go back to her typical diet. However, it didn’t feel right anymore. “Being vegan was not anything I ever wanted to be,” Chastain explained. “I just really was listening to what my body was telling me.”

Meanwhile, so long as she remains attuned to her body and its needs, it seems Chastain would be just fine.

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