Chris Hemsworth says he will "take some time off" from acting when he finishes promotion for his latest show, after discovering he has "an increased risk of Alzheimer's disease".
The 39-year-old Thor star got the news while filming his new documentary series Limitless, after taking a series of genetic tests which showed that he had two copies of a gene called APOE4, from both his mother and his father, which has been linked to an increased risk of developing the degenerative brain disorder.
A 2021 study showed that only around 2-3% of the population have both copies of the gene, which makes them around eight to 10 times more likely to develop Alzheimer's.
The Australian actor told Vanity Fair the diagnosis was his "biggest fear," but added "it's not like I've been handed my resignation".
While the findings are by no means pre-deterministic, they are considered a strong indication that the person could go on to develop the disease.
Hemsworth told the publication he was informed of his diagnosis off-air, and given the option by the producers not to talk about it in the show, but decided he wanted to share the news with other people to "motivate them to take better care of themselves" and highlight "preventative steps" available to combat Alzheimer's.
He said the news "really triggered something in me to want to take some time off" and that he plans to return home "to have a good chunk of time off and just simplify. Be with the kids, be with my wife".
Hemsworth has three children with his Spanish actress and model wife, Elsa Pataky, and they live in Byron Bay, Australia.
The actor - whose siblings Liam and Luke are also Hollywood stars - did not say whether his brothers, or parents, have gone on to be tested.
He said it's possible his children - daughter India Rose, 10, and twin sons, Sasha and Tristan, eight - may want to get tested in the future to see if they have the double gene too.
Hemsworth's grandfather is currently living with the disease, and he described him as "a really friendly guy," adding: "I'm not sure he actually remembers much anymore."
Hemsworth's next two big films will be the Mad Max: Fury Road prequel Furiosa, and Extraction 2, both of which are in post-production.
Limitless, which is made by National Geographic, aims to uncover the secrets of longevity, presenting Hemsworth with extreme challenges, including walking on top of a skyscraper and meeting with a death doula.
Limitless With Chris Hemsworth is available now on Disney+.