Hibernation vs Cryopreservation

Nearly all plants go dormant when temperatures are low. During dormancy, growth stops and the plant remains in a state of rest until good growing conditions return.


What exactly is hibernation? If you have some memories from your school days, you may remember that some animals, like chipmunks and bats, hibernate. They go into what is usually described as a long “deep sleep” in order to reduce their metabolism. This way, they cut down their need for food (that is less available in winter) and survive until the temperatures rise again.

How hibernation works

Hibernation is a survival behavior. When the food supply reduces and temperatures become more rigid, animals react to it by migrating to a warmer place or hibernating. There are several factors that trigger hibernation. Some animals have an internal biological calendar (circannual rhythms) that tells them when to hibernate. Others are triggered by the shortening of daytime (photoperiodism). Others react to the diminution of available food.

Bears don’t actually hibernate but enter a state called torpor — which can last for more than 100 consecutive days. During that time, their urine is turned into protein

Use in medicine

Many animals undergo this process, yet there is no human being who can naturally enter a state of hibernation. Nevertheless, a state of artificially induced hibernation (called suspended animation) can bring enormous advantages in the medical field. Likewise, simply lowering the temperature and metabolic rate by a few degrees can, in some cases, save lives.

  • Therapeutic hypothermia is a treatment currently used in some hospitals to reduce damages connected to cardiac arrests and strokes. When the heart stops beating, the tissues (like the brain) get damaged because of the lack of oxygen. By lowering the body temperature in a controlled environment, they can reduce the rate of consumption of oxygen and ATP (adenosine triphosphate) demand. This way, they have more time to get the heartbeat going before the damage kicks in.
  • Although hibernating animals do not move for extended periods of time, they do not experience muscle atrophy. Several studies are trying to understand how they manage to minimize loss of muscle mass. This discovery could help treat muscle disorders and help patients who are bedridden for long periods.
  • Likewise, understanding the lack of bone deterioration in hibernating animals, even after long sedentary periods, could lead to new ways of treating degenerative bone diseases, like osteoporosis.
  • Induced suspended animation could help treat cancer. The lowered metabolic rate could slow down the spread of tumors inside their tissues, giving the doctors more time to treat the patient. At the same time, by reducing healthy cells’ need for oxygen, it would allow the use of higher doses of chemotherapy. This would be fatal for non-hibernated patients.


Now, human cryopreservation (aka biostasis) is a bit of a different topic. As hibernation, cryopreservation allows the reduction of metabolic rate. Yet, cryopreservation goes a step further, to the point it completely pauses any biological activity. The result is that, while during hibernation the body still needs a lowered amount of energy, during cryopreservation it doesn’t. On the one hand, the cryopreserved person can be kept in this condition for an indefinite time. On the other hand, as there is no activity, an external force will eventually be needed to reactivate metabolic activity and vital functions.

Why cryopreservation is not freezing

Cryopreservation and freezing are two different processes — and one of the main aims of the former is to prevent the latter from happening. In fact, during freezing, the water contained in the tissues freezes, forming ice crystals. These have sharp edges, which damage the tissue. Once thawed, the tissue becomes mush.

Ice formations have sharp edges

Possible life saving procedure

Once cryopreserved, our patients can remain in this state indefinitely. However, the main purpose of biostasis, of course, is not to keep patients preserved forever. The ultimate goal is to one day revive them.

Successful revival would completely revolutionize the healthcare system


Human cryopreservation is only one part of the process. As with hibernation, if we couldn’t bring people back from this induced comatose state, we wouldn’t benefit from this procedure. Similarly, in order to benefit from cryopreservation, we must be able to successfully achieve future revival. At the moment, the necessary technology has not yet been developed. Thanks to the efforts of cryonics institutes, such as Tomorrow Biostasis, there is a chance that we will be able to achieve this goal and completely change medical institutions.



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Tomorrow Biostasis GmbH

Tomorrow Biostasis GmbH

We are a Berlin based longevity company committed to advancing Biostasis technology and promoting it in a simple and transparent way. www.tomorrowbiostasis.com