People looking for a way to live forever is a tale as old as time. As much as humans have searched for the fountain of youth or the philosopher’s stone, however, we have never achieved immortality (that the general public knows of). But we are not without hope: Cryogenically freezing people is the closest we have come to eternity.

If Demolition Man can survive cryogenic freezing, why can't you? Credit: A cinematic masterpiece

A Life Noggin video explains the process of putting someone into a deep freeze after they die — they are given oxygen and blood until being packed in ice, with a dose of anticoagulant to keep the blood from congealing. From there, experts use a sort of human antifreeze to stop ice crystals from forming and damaging the tissue before the body is put into an extremely cold container of liquid nitrogen.

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The idea is that one day we will have the technology to bring these frozen dead people back to life, then cure them of whatever killed them years earlier. It sounds crazy, but Life Noggin explains that “practically every type of cell has been successfully cryopreserved,” and experiments with a couple of animals show promising results. Roundworms that were cryopreserved and brought back to life still showed the same learned behaviors they had previously, and sheep ovaries have been frozen and transplanted.

Some people have already put their faith in cryogenic freezing. A British teenager who died of a rare cancer in the fall made headlines by winning a court case that would allow her to be frozen against her father’s wishes. The 14-year-old expressed that she wanted to be cured and woken up “even in hundreds of years’ time.”

There are challenges to waking up a frozen person, but perhaps one day scientists will figure it all out.

See also:

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