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7 June 2016

Cryosleep: Fact or Fiction?

Freezing biological material to preserve it is a time-tested practice, but that material is usually a far cry from alive, and usually the idea is that you’re going to eat it at some stage or another. Since the days of ancient Greece, there have been records of the use of freezing as a method of saving people from injury or death. Our understanding of medicine and biology may have been far, far more limited then, but there was a semblance of logic nestled in there somewhere.

Img source: howitworksdaily.com
Experiments with induced hypothermia began in the early 20th century, and in 1945 a paper was published which detailed the act of treating brain damaged patients by cooling them to slow their metabolism and aid recovery. Suffice to say, it didn’t really work, but it opened up a range of new ideas and possibilities.

Since then there have been several cases of people entering a state of extreme hypothermia and not only surviving, but making a full recovery. In 2006, a breakthrough arrived, as a Japanese hiker slipped while climbing Mt. Rokko and broke his pelvis. So far, so awful, but this where it gets crazy. He was found 24 days later, exactly where he’d stopped after slipped, having had no food or water, his body temperature down to a staggering 22°C (35 or below is considered to be hypothermic). Not only did he live, but he actually made a full recovery, his body having effectively gone into a state of hibernation.

Many animals do this, but it had never been observed in humans to this level of extremity before the Mitsutaka Uchikoshi case. It was already known that ice had remarkable preservation qualities, a prime example being Juanita, or the Incan Maiden, a 500-year-old mummy found in Peru in 1995. She was remarkably well preserved, so well preserved in fact that scientists were able to examine the contents of her stomach and figure out that the last thing she ate was a vegetable stew, about 6 hours before she died.

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Many people have arranged to have their bodies frozen after death, in the hope that they could be resurrected in the future when we gain the technology to do so. If you’ve ever seen Vanilla Sky, that will be a familiar notion. As of 2 years ago, 250 people have been cryopreserved in the US alone, with a further 1500 people to be frozen upon their deaths. Obviously, none have been revived yet, but the further into the future people wait to be frozen in this way, the more likely they are to be thawed out successfully, as the technology develops to further minimise tissue damage.

That’s one side of it, but the other is cryosleep, or the act of freezing someone while they’re actually alive in order to treat them medically, or in the future, permit long distance space travel. It might seem like the stuff of science fiction, but science fiction has preceded science fact more than once (tractor beams, warp drive, bionics, eugenics, I could go on).

Induced hypothermia is becoming a more widely accepted medical treatment now, but there’s still a lot of debate as to just how effective it really is. Induced hypothermia is one thing, but torpor is quite another. It’s another term for true hibernation, and the school of thought is that we can induce it in ourselves. Hypothermia is the result of the body trying to warm itself back up, a torpid body would not attempt this, merely reduce metabolic function to the bare minimum.

We already induce comas in patients when we need to, but this is a whole different ball game. Research suggests that it will involve inducing a state which humans haven’t needed to go into since long before we were human. Studies into animals which do have revealed that the adenosine A1 receptor, which factors into regulating body activity during sleep, is a key trigger in hibernation. Stimulating it could potentially induce a hibernation state; it was recently successfully tested on animals.

In terms of space travel, it would not only be helpful for long distance travel (which even with warp drive, will still be a consideration), but it will massively aid weight saving, as far less resources will need to be brought on board. Research initiatives have been set up all over the world, but the issues are two-fold - funding and permission for human testing. Fiddling around with receptors in the brain is a risky business, and even if you can find willing volunteers, the challenge is proving that the research is important enough to warrant that kind of risk and expenditure.


If we assume space travel is a necessity to maintain human development and survival, this will have to be addressed at some stage. Even with that, we’re talking about putting people into cryosleep for a few weeks, maybe a month, but we’re still a far cry from freezing people for centuries. Such an idea stretches beyond what even the most resilient animals are capable of. 


Callum Davies

Callum is a film school graduate who is now making a name for himself as a journalist and content writer. His vices include flat whites and 90s hip-hop.