‘Limitless’: Chris Hemsworth’s High Risk for Alzheimer’s Revealed, Actor Announces Break From Acting

Chris Hemsworth is no stranger to death-defying acts. The Hollywood star has spent the past decade as Marvel’s Thor, the Asgardian God of Thunder. But while filming his new Disney+ series, Limitless, Hemsworth received a heavy dose of mortality when he learned of his high risk for Alzheimer’s. The Australian A-lister swiftly announced a break from acting following the series premiere. 

Chris Hemsworth’s documentary ‘Limitless’ is on Disney+

Chris Hemsworth, 'Limitless,' and Alzheimer's
Chris Hemsworth attends the premiere of ‘Limitless With Chris Hemsworth’ on Nov. 15, 2022, in New York City | Dia Dipasupil/Getty Images

The concept behind National Geographic’s documentary Limitless on Disney+ is a bit of a catch-22. First, the series’ main goal is not to defy death but to prolong life. Yet to do that, one must learn to defy (or stave off) death. Tricky. 

So Limitless targets Hemsworth’s weak spots — his stress, lack of sleep, reliance on technology, etc. — and teaches him how to better manage today’s silent killers. 

The quest is fascinating. When trying to manage his stress, Hemsworth trains to walk on a crane suspended from the top of a skyscraper in Sydney, Australia — an intensely stressful activity even for those not afraid of heights. The series also investigates how extreme temperatures, fasting, physical strength, and memory work might produce longevity. 

During Limitless Episode 5, “Memory,” the series takes a heart-wrenching turn. 

While filming ‘Limitless,’ Chris Hemsworth discovered his high genetic risk for Alzheimer’s

Originally, Limitless Episode 5 was supposed to show Hemsworth learning his results from various blood tests on camera. Then he and the doctor would discuss managing what might plague Hemsworth from within. But the actor tells Vanity Fair that his results led to a rerouting of that plan. 

Hemsworth says Limitless’ longevity doctor, Peter Attia, called the series creator, Darren Aronofsky, and said, “I don’t want to tell [Hemsworth] this on camera.” Attia and Aronofsky then called the actor to tell him the news privately. It was Hemsworth who decided to include the information in the episode. 

His bloodwork showed he has two copies of the APOE4 gene, one from each side of his family. That means Hemsworth is eight to 10 times likelier to develop Alzheimer’s disease than the average person. The news hit hard, even with Hemsworth aware of his results by the time they are read to him on camera.

Only days after the series premiered on Disney+ and his Alzheimer’s risk came to light, Hemsworth announced he was stepping back from acting to spend time with his family. 

Marvel halted filming on ‘Limitless’ because it ‘might kill’ the star

Chris Hemsworth wasn’t the only one made to reckon with his mortality during the filming of Limitless. During episode 4, “Strength,” he began training for a rope climb. But this was no ordinary rope climb — the rope was hanging from a cable car suspended in mid-air.

During an interview on Jimmy Kimmel Live, Hemsworth describes how he injured his ankle while training for the stunt. It was then that Marvel “stepped in and said, ‘No. The show that might kill him, you can do that after our film.'” But by the time Hemsworth could resume filming the stunt, he was Thor-sized, making the activity much more difficult. “It became the will to fistfight to try and get up the thing,” he recalls.

Yet despite Limitless’ headline-making, death-defying stunts, the series is about much more than watching Thor reckon with being mortal. Slash Film reports that “as Hemsworth approaches 40, it gets tougher, and the body succumbs to time on some level. Hence, his fascination with wanting to pursue longevity.” 

But the series is really about all of us trying to live our healthiest, fullest lives. And in that spirit, perhaps the biggest takeaway is to take a page from Hemsworth’s book and enjoy the things that matter most. 

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