Imagine setting your alarm one night and waking up light years away on another planet. It sounds like
science fiction, but scientists are hard at work trying to unlock the secrets of human hibernation.
And if they succeed, it could be a game changer for everything from
curing diseases to deep space travel. Hibernation is just scientifically weird.
It’s more than bears crawling in a cave and hitting snooze.
When animals go into hibernation, they exhibit symptoms similar to those of
diabetes and Alzheimer's. Bears, for example, become resistant to insulin, and their brains
tiptoe the line of neurodegeneration. But when they wake up, they’re “cured.” If scientists can
figure out what's so special about hibernators, they may be able to use this knowledge
to treat diseases that afflict us humans. So, what would it take for humans to actually
hibernate? To answer this, we first need to know why some animals hibernate in the first place.
For warm-blooded animals, it can take a lot of energy to maintain a constant body temperature.
That can be a really big challenge when their source of energy, food, is scarce.
Hibernation is a survival mechanism that conserves energy by lowering the body’s core temperature,
slowing the heart rate, and shifting into a lower metabolic state, known as torpor.
For example, when arctic ground squirrels enter hibernation
their temperature plummets from 37°C to -3°C and their metabolic rate drops by about 99%.
Humans, by comparison, are stuck with a relatively fixed body temperature of 37°C. Aside from minute
variations, like when we sleep, our temperature only changes as a way to signal danger. Like
when we’re sick, we get a fever. Just a few degrees off either way can mean death.
But this isn’t a hard and fast rule. In 1999, a woman fell while skiing, crashing head first into
a frozen stream. When medics arrived 80 minutes later, her body temperature had dropped to 13.7°C,
rendering her clinically dead. But she miraculously survived! The extreme cold lowered
her metabolism so her brain wasn’t oxygen-starved. Lack of oxygen can lead to permanent brain damage
in a matter of minutes… usually not enough time to make it to the operating table.
An ongoing trial led by researchers at the University of Maryland is testing this
idea of suspended animation — otherwise called emergency preservation and resuscitation, or EPR.
The idea is that it can help patients whose hearts have stopped due to excessive blood loss.
By replacing their blood with ice-cold saline, it lowers their body temperature
to 10°C.
This decreases the body’s need for oxygen, buying the operating team more time.
After surgery is complete, the body is warmed up and the heart is restarted. The trial is expected
to wrap in December of 2022, and they’ve already used the technique on a handful of patients.
And NASA is working to take suspended animation to the next level. In 2014, the agency
funded research on extended human hibernation and found that it would cut down on the amount
of food, water, and supplies needed, making deep space travel more practical. Because in theory,
if we lowered your temperature enough, eventually your metabolism would come to a standstill.
According to Spaceworks, the company contracted by NASA to do the study, astronauts could safely
be kept in a hibernation-like state for 14 days with current medical capabilities. A four-person
crew could work in shifts with three in cryogenic pods, while one runs the ship.
Expanded human trials are expected in 2024.
So, we may not be able to slow a person’s metabolism for so long that they can actually
hibernate…yet. But given time, we all might be hibernating sometime soon.
Another thing scientists are looking at for deep space travel is artificial gravity.
If you want to learn more, watch Julian’s video here. If you had the option to hibernate,
would you? Let us know down in the comments. Make sure to subscribe and thanks for watching.