Chris Hemsworth on life changes since discovering his risk of Alzheimer's

Chris Hemsworth is opening up about how he coped with the discovery that he has a significantly greater risk of developing Alzheimer’s disease.

During a recent interview with Sky News, the Australian actor recalled his learning from a genetic test done in season one of Limitless: Live Better Now that he was eight to ten times more likely than average to develop the brain disorder.

"It was just kind of this point in my life where up until your 40s, you're kind of gathering data and information and it's all reactionary and then you get to a point where you think, oh some of this sort of identity that I've sort of built doesn't hold true anymore," Hemsworth said in the interview.

The revelation prompted Hemsworth to reconsider his motivations and focus on deeper questions about purpose, contribution, and meaning. He shifted away from simply “collecting” achievements toward spending more time with loved ones.

Hemsworth had initially joined the National Geographic series as its “guinea pig,” taking on extreme challenges to push his body and mind. But the personal discovery changed the tone of his involvement.

By season two, Hemsworth said he took a more active role in shaping the episodes, steering them toward topics he was “deeply curious about” and making the process more personal.

“I was much more committed to the experience,” he explained. “In the first season, I felt uncomfortable because I was surrounded by experts and knew nothing about the topics. I felt like an imposter. This time, I was educated, prepared, and more invested — and I enjoyed it a lot more.”

Research shows about one in 50 people inherit two copies of the APOE4 gene. Nearly all double carriers show early signs of Alzheimer’s — which causes dementia — by the age of 55.