It is known that a person can do without food for quite a long time. Physiologists repeatedly conducted experiments with different periods of fasting with the participation of volunteer testers and determined the reserve capabilities of the human body.
So, to test the possibilities of prolonged starvation in the conditions of autonomous existence in the summer of 1984, seven members of the Extreme expedition went on a 500-kilometer trek through the mountain rapids of the Southern Urals, without taking any food supplies with them. This experiment lasted fifteen days, the participants of which successfully passed all the tests.
If we exclude the fasting record set by the American Elaine Jones, who weighed 143 kg and remained without food for 119 days, then people who voluntarily doomed themselves to complete starvation can withstand no more than 60-70 days. In 1981, a group of Irish prisoners in a Long Cash concentration camp went on a hunger strike to protest the brutal regime of jailers. Their leader, 24-year-old Bobby Sands, began it on March 1, his death occurred on the 66th day.
People who find themselves in a deserted area with a small supply of food, first of all, need to take into account all the available products and distribute them into small portions with a calorie content of about 500 kcal. It is not difficult to calculate, knowing that 1 g of fat gives 9.1 kcal, 1 g of protein 4 kcal, 1 g of carbohydrates 4 kcal.
At the same time, if possible, it is necessary to use as much as possible everything that the surrounding nature gives: meat of animals, fish, reptiles, large insects, edible wild plants. Emergency stock products are best left on a rainy day. But first of all, everyone who finds themselves in conditions of self-survival should clearly understand the reserve capabilities of their body.
The reserve capabilities of the human body.
The human body is a unique construct of nature. Each organ and organ system has enormous potential. Let’s talk about these bodies in more detail..
Every second, over 100,000 chemical reactions take place in the brain, requiring a huge amount of energy. With a lot of brain tension, as many calories are burned as with active muscle work during exercise. That is why mental work is no less debilitating than physical. Since there are no nerve endings in the brain, it can be burned, frozen and cut, without causing even the slightest sensation. In the practice of neurosurgery, operations are often performed without anesthesia..
Mucous membrane of the nose.
This is the first line of defense against millions of bacteria constantly trying to enter the body. Bacteria that survive despite the strong exposure to chemicals in the mucous membrane go out with the secretions or are swallowed and end up with stomach acid. Against pollen grains, another protective system works. Reacting with the mucous membrane, they form chemicals that cause a tingling sensation, which, in turn, provokes sneezing, while the particles fly out of the nose at a speed of more than 150 km / h. Every few hours, the size of the blood vessels in the nasal passages alternately changes, so one passage is always wider than the other.
This is a miracle of miracles. When we blink, the eyes are washed by the antibacterial fluid secreted by the lacrimal glands. Tears caused by irritants differ from tears caused by grief, which contain 24% more protein. In both cases, they have prolactin hormone that stimulates the formation of milk. Perhaps this explains why women cry more often than men. Crocodile tears occur during salivation. As a rule, they are the result of trauma, as a result of which nerves from the salivary and lacrimal glands intersected. Unhappy in anticipation of food literally cry with burning tears.
One square centimeter of human skin contains approximately 3 million cells, 95 sweat glands, 14 sebaceous glands, 10 hairs, 90 centimeters of blood vessels, 2900 sensitive cells and more than three million microscopic organisms. The blood vessels of the skin instantly narrow in the event of a cut or pressure on the skin. To verify this, swipe the ruler over your arm. The white line that appears on the arm is explained by a sudden outflow of blood, in the case of a cut it limits bleeding. A few seconds after you take the ruler, the vessels will fill with blood again and the line will turn red.
The body constantly discards dead skin cells and replaces them with new ones. Dust in the air in an ordinary house consists of 75% dead skin cells. The body cools due to the evaporation of sweat. On a typical summer day, about 2 liters evaporate. However, on high humidity days, sweat may not evaporate. As a result, the time a person can stay in moist air is sharply reduced. In completely dry air, a person can withstand temperatures up to 90 degrees for one hour or so. In humid air, it can endure a temperature of no more than 45-50 degrees, and then only for a short time.
One of the most potent corrosive substances, even safety razor blades dissolve in it. In order not to digest itself, the stomach changes its inner shell every three days.
This is a car with an incredibly high efficiency. To ride a bicycle at a speed of 15 km / h for one hour, the body needs about 350 feces from food. This energy is equivalent to the energy of three tablespoons of gasoline. A person hears sound in the range from 20 Hz (lower than double bass) to 20,000 Hz (higher than piccolo). Oddly enough, the noise of blood flow in the vessels of the head and neck is within earshot, but we do not hear it. Doctors cannot explain why. When we speak, the sound of our voice reaches the ears mainly through the bones, which slightly change its timbre. That’s why many people don’t recognize their voice recorded on tape: only sound transmitted through the air is recorded.
It is unity in diversity. This is both a temple, a warehouse, a pharmacy, an electric company, a library, and a sewage treatment plant. This, according to the English prose writer and poet Joseph Addison, is a system folded so amazingly that it has become a genuine motor for the soul. The body has great reserve opportunities for life in the environment. Man’s will and courage help him to emerge victorious in difficult, extreme situations in nature. However, the reserve capacity of the human body is not unlimited. There are limits beyond which changes in the functions of organs and tissues become irreversible, and then death occurs.
A person who is active for about 8 hours during the day spends about 50-70 kcal per 1 kg of his weight. If a person weighs 70 kg, then the calorie content of the daily diet should be 4200 kcal, and at 60 kg, the weight should be 3600 kcal. In order to make up for energy loss, a person needs to consume a certain set of food products. Food provides human energy needs associated with physical activity and exposure to cold. The need for food depends mainly on the intensity of the load and temperature.
For normal life and the struggle for survival, the body needs a systematic replenishment of energy costs through nutrition. If this is not possible, the body is forced to adapt to new conditions at the expense of its own reserves. Adaptive reactions of the body are expressed primarily in reducing energy consumption, reducing intensity and slowing down the metabolism. At the same time, oxidation processes become leading. The alkaline reserve of blood decreases, and in the urine the content of ammonia rises, which the body uses to neutralize acidic metabolic products.
Urinary excretion of minerals, especially chlorides, is reduced. The nitrogen content in the urine drops sharply. Pulse and breathing become less frequent, blood pressure decreases. Deprived of incoming fuel from the outside, the body after appropriate adjustment begins to spend its internal tissue reserves and reserve capacity. They are pretty impressive. So, a person weighing 70 kg has:
fat cells about 15 kg (141 thousand kcal);
muscle protein 6 kg (24 thousand kcal);
muscle glycogen 0.15 kg (600 kcal);
liver glycogen 0.075 kg (300 kcal).
Thus, the body has energy reserves of approximately 165,900 kcal. According to physiologists, it is possible to use up reserve capacity by 40-45% before the death of the body occurs. If you take the daily energy consumption of the human body at rest for 1800 kcal, tissue reserves should be enough for 30-40 days of complete starvation. However, in calculations, one more important factor should be taken into account: nitrogen loss.
It is known that the brain must receive daily energy equivalent to 100 grams of glucose. Fats (triglycerides) provide only 16 g of glucose, and the rest is produced from glycogenic amino acids during the breakdown of muscle protein, which leads to daily losses of 2.5 g of nitrogen. The adult body contains approximately 1000 g of nitrogen. A 50% reduction in this stock is incompatible with the body’s further activity..
Based on the book Methods of Autonomous Human Survival in Nature.
Maslov A.G., Konstantinov Yu.S., Latchuk V.G..