It is known that there are several conditions for the human body to survive. Have you ever wondered how long you can live without oxygen, food or water, without heat or sleep? We will give answers to these and many other questions. There is a difference between the need for survival and the desire to prosper. Thriving and growing is a consequence of basic survival. As long as basic needs are met, the human body enjoys comfort and growth.
In certain situations, you must prioritize your basic needs rather than your basic comfort and prosperity. For example, if you experience an 8 Richter earthquake, you will not be looking for your novel at bedtime, but an immediate exit from the building or area in danger of extinction. Your life is on the line and your basic needs have maximum priority for that moment.
We will explore this field more thoroughly and talk more about these basic needs of human survival in more detail.
Oxygen, atmospheric pressure and water.
The top of the list is reserved for the oxygen. Breathing is our most immediate need. How long can a human survive without oxygen? Some athletes can live without oxygen for up to 6-7 minutes. A normal person – no more than 4-5 minutes. While we breathe, oxygen reaches every cell and organ of our body and oxygenates the bloodstream.
Without enough oxygen, the first organ that suffers most is the brain. Without oxygen for more than 15 minutes, the brain damage is so severe that a person can not recover afterwards. This is called cerebral hypoxia and is irreversible. If after 15 minutes your body receives oxygen, it is possible that your other organs can be revived, but the person will be # 8216; brain death “.
There may be other reasons for your body to have insufficient oxygen in the bloodstream. Usually, these are medical reasons, such as stroke and cardiac arrest. If a person is anemic, they do not have enough oxygen absorbed in the bloodstream and their organs can suffer permanent damage over time (it can take a few decades).
It should be mentioned that the human body on average needs certain atmospheric pressure For optimal body functions. This is one of the reasons why a human being (or indeed, any creature) can not survive more than a day or two above 8000 meters above sea level. There may still be oxygen there, but the body can not optimize its use.
It is speculated that Nepalese are better able to survive longer at such altitudes due to a change in DNA. Your blood has fewer red blood cells and, contrary to logic, this is the reason why they extract and absorb oxygen better. Therefore, the Nepalese are considered anemic at sea level, but in reality they are not.
Next on the list is Water. This is the second most important element for the body to survive. On average, the lifespan of a human being without water can be estimated from 3 to 4 days. There are some factors that can lengthen or shorten this period. Temperature, for example, can be an important factor. The hotter you are, the faster you lose fluids from your body, as you sweat more. It is estimated that from 80 degrees Fahrenheit, a man can survive up to 10 days.
For every 5 degrees more, its life is shortened by a whole day. Your chances of survival are also affected by your physical effort. The more you move and the more effort you put into your activity, the faster you will lose water from your bloodstream.
You should know that, as a human being loses 2-3% of water, this means up to 20% thickening of the blood. The blood loses its volume and becomes thicker. It moves slower through the body and takes more time to reach more distant areas such as the fingers.
As a result you would have cold fingers. Not only that, but as some capillaries are thinner, blood can not pass through them and can obstruct the passages to the vital organs. The capillaries of the brain are very thin and blood can not reach the brain if it is too thick. This leads to loss of focus and even unconsciousness, in extreme cases.
You also need to know what water does to the body (when basic needs are met) to know what functions are affected by dehydration.
Water helps eliminate toxins and impurities from the body (through urine and sweat); It forms the saliva that is needed for digestion; helps the body maintain normal temperature and prevent overheating; it helps the digestion process, which requires a certain amount of liquids to process the nutrients; keeps joints lubricated and improves motor functions; helps the production of hormones (in the brain) and neurotransmitters; provides the basic element for each cell to survive and grow.
This quick overview gives a general idea of the vital processes that are supported by the presence of water in the body. During dehydration, each of these processes suffers and eventually goes off over time.
Food and shelter
The following two needs can be interchangeable and change their place of relevance depending on whether one is satisfied or not. Therefore, these two needs are food and shelter. In general, a man will not seek refuge if he is deadly hungry, and yet the protection of the elements goes hand in hand with immediate survival. What happens if a hail storm hits, or you’re in a heavy snowstorm? You will not be looking for food in those situations, even if you’re hungry.
So, coat It is the next important need for a man to survive. In this category is also the need to hot. It will not survive more than a few days in sub-zero temperatures even if it has food to eat, but it has no shelter or protection. There is a certain balance when it comes to the temperature that keeps the body in a normal state.
Body temperature, which fluctuates below or above these degrees, puts the body in survival mode. A stronger deviation leads to death. Then, the best body temperature is 98.7 degrees Fahrenheit. With 7 degrees below you lose consciousness. 7 degrees lower and the body can no longer regulate the internal heat. At 82 there is a total muscle degradation and finally death at 79.
However, on the other hand, if the temperature of your body increases to 107 degrees, you will suffer neurological damage. More than 111 degrees causes the brain to overheat and this eventually leads to death. All these scenarios can be avoided with adequate protection against cold or heat. It is estimated that cold conditions can reduce body fluids (and lead to dehydration) as quickly as warm weather conditions.
When we talk about the internal temperature of the body, we must also address the temperature outside and how human bodies survive in degrees too low or too high. It is known that the body can adapt to certain changes, but it must happen gradually. For example, 140 degrees F (60 degrees Celsius) in combination with extremely wet conditions can cause death after 10 minutes of exposure. This condition is called hyperthermia.
As for cold weather, humans are usually well-equipped with clothes and -29 C may be tolerable with adequate clothing. But there is rarely cold air. Usually the winters are accompanied by wind. As we add the y # 8216; Wind cooling factor ‘, the previous temperature can be felt as -45 only with a slight wind breeze. Add a little more (25 mph) and it feels like -66. That’s when the exposed skin suffers freezing in minutes.
Apsley Cherry-Garrard tells her story of how -47 F (-43 C) left her mittens to grab a rope (with her own hands). He did his work in a few minutes, and only a few hours later, when he was already inside, in a warm room, he saw several blisters on his fingers. This is superficial freezing and damages only the skin layer. It is not dangerous as the damaged skin falls off and the new skin grows. But it is a good example of the ease with which low temperatures can damage the body.
On the other hand, if you are, for example, in cold water (around the freezing level), you may be able to survive for no more than 30 minutes. Because cold affects proper blood circulation, there is not enough oxygen to reach your brain. This causes drowsiness and can lead to even more rapid death and hypothermia.
As we discussed earlier, food It is also part of the basic survival needs. In general, an average man can survive more than a month without any food (sometimes even more than that). This period of survival depends on some things: fat reserves, muscle mass and the state of internal organs.
During starvation the process is as follows. In the first 3 days the body uses only the reserves of fat. Depending on that, this period may be longer or shorter. Then, the body goes into a ketone stage, when it uses the fat reserves of the liver, which are called ketones (fatty acids). The body not only uses the reserves of the liver, but can also resort to the intestines. This is one of the reasons why it is difficult to feed someone without causing more problems.
The intestinal walls and muscles are damaged by the long period of starvation and are still not repaired in order to function properly. This process takes approximately 2 weeks. It depends again on the individual’s reserves.
The last stage is when the body eats the muscles. It really does not matter what kind of muscle it will consume, but eventually it leads to damage to the muscles of the heart. As a result, the heart weakens and can no longer pump blood. Then it simply goes off. Literally, the body eats itself to prolong life at the expense of the organism itself.
It is often neglected, but an individual may die during starvation, not because of it, but because of its toxicity. Normally the liver is the organ that processes the toxins. To eliminate them, you need nutrients to break down and neutralize these toxins. If the individual goes through a process of starvation without nutrients entering the body, the liver has no way to process and decompose the toxins and, finally, it goes off. This quickly leads to a painful death.
However, we must point out that the majority of people who suffer from these conditions do not die directly from starvation, but from infections. The natural defenses of the body decompose. The body can not support its own defense systems if it does not have fuel (nutrients) to do so. Usually, the individual suffers abdominal edema or swelling of the extremities. This means collecting fluids in certain areas of the body (predominantly the abdomen and extremities). As a result, infectious diseases attack the body and eventually cause death.
The importance of the proper sleep cycle.
The next most basic need is sleep. In the past it was not considered a basic necessity and its vital importance was neglected. Only in recent times, thanks to scientific research and published data, we know that sleep is, in fact, as vital as all previous needs. The longer the individual is deprived of adequate sleep, the worse their condition will be. Combined with the lack of one of the above needs, sleep deprivation can be fatal. On the one hand, it reduces the defenses of the immune system and can cause a variety of infections and inflammations throughout the body.
Within the first 24 hours the individual will suffer headaches. After 72 hours, one may experience difficulties in spatial orientation and memory loss. Cognitive skills suffer even more after 96 hours. As we move forward, after 144 hours, self-control deteriorates and hallucinations occur.
As it is impossible to prove how far a human organism without sleep can live, we can only assume it. But one thing is certain, the body needs repairs and while we sleep, the body reconstructs the damaged DNA. It leaves the survival stage so that it can enter repair mode. Without it, the damage, which had already occurred and has not been solved, can continue to accumulate in the system and this can cause illnesses and infections, some of which, if not addressed, can be fatal.
There have been some laboratory experiments with mice, which show that sleep deprivation leads to death. There has also been a case with Randy Gardner, who decided to try to stay awake as long as he can. His experiment lasted about 11 days, until he succumbed to hallucinations and stopped the experiment, since he could have died if he had not.
In another case, a Chinese man also tried to stay awake to see the European Cup, in every game of it. He stayed awake for 11 days, but eventually died. However, it should be noted that he was also drinking alcohol and smoking, which may have contributed to the breakdown of his body.
In laboratory tests on rats, scientists discovered that as sleep deprivation progressed in time, the mice’s metabolism gradually accelerated. This condition is called hypermetabolism and is linked to sleep deprivation. During this condition, the body’s metabolic rates are very high even during rest. This burns all the calories and fat reserves of the body for a very short time, leaving it exposed to infections (since the immune system weakens).
Do you know your limits?
In addition to these five basic needs, there is one more that can be addressed. For example, how much radiation can we maintain (in the event of an explosion of a nuclear reactor)? It is estimated that 5-6 Sv (Sieverts) radiation (in several minutes) will destroy many of your cells, and too fast for them to regenerate in time, to preserve the body.
For comparison, workers at the Fukushima nuclear reactor maintained a radiation of approximately 0.4 to 1 Sv over the course of an hour, as they worked after the damage of the reactors. They are still alive today, but they live with a very high risk of developing cancer in the coming years.
On the other hand, an interesting fact is that a human being who is exposed to the sources of natural radiation (uranium in the soil, radiation from the sun and cosmic rays and gamma rays, etc.) and supposedly, for example, assume that humanity eradicated all diseases and cancer, can not live more than 4000 years. The body will suffer a gradual damage and the DNA can no longer be repaired over time, therefore, death would occur. This means that immortality can not be achieved.
All of the above situations, in which the human body is pushed to the limit, are examples of how durable and how fragile we are. However, as long as you are aware of the limits of your body, you can have a little more control over the situations that you encounter in your life. Do not push your limits too hard or you may cross the survival limits. In our modern times there are many people who practice extreme sports and test their limits, trying to push them more and more. Many of them die as a result; others realize that their bodies are not invincible and respect the hardness of nature.