Life hacker invites you to find out what existing misconceptions about the protective system of our body can seriously harm our health.
Myth number 1. Vaccinations will not help
The introduction of vaccines into the human body is carried out in order to provide it with protection against dangerous pathogens. The vaccine is given to a healthy person in order to “arm” the body with the means of combating infection in advance.
After the components of the vaccines enter the body, the same mechanism starts that works when an infection occurs. Immune cells - B-lymphocytes - trigger the production of antibodies, immunity molecules, which serve as foreign labels and help quickly rid the body of pathogens.
When vaccination does not start active actions to destroy the pathogen, since vaccines can not cause disease. This is a kind of “rehearsal” of the actions of the immune system in response to the ingestion of a dangerous infectious agent.
After inoculation and synthesis of the necessary antibodies, the body already “gains time”: its B-lymphocytes “remember” which antibodies should be produced when meeting with this or that pathogen. These antibodies will successfully allow the components of the immune system to detect the threat and remove it from the body before the disease develops.
Licensed vaccines are carefully scrutinized, and once they enter the market, they become a constant subject of repeated checks and reviews. Vaccination does not give a 100% guarantee that the vaccinated person will not get sick, but this procedure significantly reduces the likelihood of being infected with a dangerous pathogen.
According to the WHO (World Health Organization), every year immunization prevents from two to three million deaths from diphtheria, tetanus, pertussis and measles, and the dangerous smallpox virus was completely defeated with the help of vaccinations.
Myth number 2. Children should be kept sterile because they do not have immunity.
In fact, newborns have immunity, but it develops gradually over several years according to the genetic program embedded in the DNA. It is realized as the child grows up.
While the fetus is in the womb, maternal immunity protects it. Lymphoid organs are gradually formed: bone marrow, thymus, clusters of diffuse lymphoid tissue, lymph nodes, spleen. In addition, in the liver, spleen and bone marrow of the fetus, immune cells are formed - lymphocytes, neutrophils, eosinophils.
In the first three months after the birth of the baby, exclusively maternal antibodies protect. The transfer of antibodies of type lgG occurs in the last trimester of pregnancy. Maternal antibodies decay over time, and by 3-6 months, many of them cease to function.
The baby's skin, which is sensitive to even minor injuries, is covered with vernix caseosa vernix. This waxy mixture is secreted by the sebaceous glands. It contains antimicrobial substances - lysozymes, defensins, psoriazins, antimicrobial fatty acids. All of them make up an antimicrobial shield that protects the baby from a large number of various pathogenic microbes.
In addition, at the time of birth, Peyer's patches are already present in the intestines of a newborn - accumulations of T- and B-lymphocytes in the mucous membrane. When microbes enter, they provoke an immune response and further help to adequately respond to foreign matter in the digestive tract.
From birth, a child has a program for the development of the immune system. For its maturation to be realized, contact with various antigens and time are required. Of course, until the immune system is fully strengthened, children are stronger than adults, at risk of contracting this or that infection. However, the desire to create "sterile conditions" for the child threatens the development of hypersensitivity reactions - allergies and autoimmune diseases.
There is a hypothesis about hygiene, according to which the development of such conditions is provoked by insufficient contact with infectious agents, symbiotic microorganisms - representatives of normal microflora and parasites in early childhood. The lack of such contacts leads to a violation of the establishment of immune tolerance - immunity to their own cells and molecules.
The immunity of children who live in conditions close to sterile may in the future be undeveloped. Evolutionarily, a person always received a certain level of load on the immune system in the form of a certain number of pathogens. If the number of surrounding antigens drops, then the body begins to attack harmless particles and compounds. For example, flower pollen or food components can cause an immune response.
It is believed that the immune system matures by the age of 12-14, when the same amount of antibodies begins to be produced in a young body as in an adult.
Myth No. 3. Immunity is strengthened by yoghurts and multivitamin supplements.
There are many recommendations in advertising and the media that convince you to buy yoghurts with bacteria, multivitamin complexes, miracle immunostimulants and much more. Unfortunately, there is no ideal and simple recipe for the prevention of infectious diseases.
Let's start with yoghurt. In commercials, we are told that immunity depends on the intestinal microflora, and yoghurts with beneficial bacteria improve the microflora, and therefore the body's immunity.
Today we know that about a thousand species of bacteria live in the human intestines, which play a crucial role in the normal functioning of the body. Long co-evolution of bacteria and the human body has led to the emergence of complex mechanisms of interaction of the components of the immune system with representatives of the microbiome.
The intestinal microflora not only aids digestion and produces the vital B vitamins and vitamin K that our bodies cannot synthesize, but also prevents the entry of pathogenic microbes by maintaining the integrity of the intestinal mucosa and physically preventing them from attaching to intestinal cells.
But the fact is that bacteria from the outside, in particular beneficial yoghurt bacteria, are not able to stay in the intestines for a long time. This was confirmed by the American researcher Sherwood Gorbach, who studied bacterial strains for more than 20 years. He was unable to find bacteria lingering in the intestines in any of the dairy cultures of America, Europe and Asia. If some strains survived after gastric hydrochloric acid, they still disappeared after 1-2 days.
Although today some probiotics have shown promising results in experiments, so far scientists have not enough convincing scientific data on their benefits.
In the United States, the FDA has not approved a single probiotic to prevent or treat any disease, including those related to the immune system.
Maybe then multivitamin supplements will help? Vitamins help the implementation of all the most important enzymatic reactions that occur in the body. In total, the human body needs 13 vitamins for normal life: vitamin A, vitamins of group B (B1, B2, B3, B5, B6, B7, B9, B12), vitamins C, D, E and K.
Vitamins A, C, D, E, and B6 have been identified as essential participants in immune-related processes. With their lack, the activation of T- and B-lymphocytes is impaired, and pro-inflammatory signaling molecules are produced to a greater extent, which in some cases can complicate pathological processes.
Unfortunately, multivitamin complexes often turn out to be useless, because synthetic vitamins in tablets are absorbed worse or not at all by our body. Some components of supplements, such as calcium and iron, cannot be absorbed together. In particular, the fat-soluble vitamins A, D, E, and K are often available as tablets that do not contain any lipids required for absorption.
Nutritionists, scientists and experts from reputable organizations such as the WHO and the FDA (Food and Drug Administration) recommend eating well and getting vitamins with food. In case of a lack of vitamins, you need to consult a doctor and review the diet and composition of the products.
Attempts to replenish the supply of vitamins on your own, without the advice of doctors, can be quite dangerous. According to dozens of scientific studies, daily excessive intake of vitamins can lead to an increased risk of developing various diseases.
Myth number 4. The brain has no immunity
The brain, like some other tissues and organs (eye cornea, testicles, thyroid gland), is called an immunoprivileged organ due to the fact that it is isolated from the main components of the immune system using the blood-brain barrier. This barrier, among other things, protects the tissues of the organ from contact with the blood, which contains cells and molecules of immunity.
Immune reactions in the brain occur somewhat differently than in the rest of the body. Since the brain is very sensitive to various injuries, its immune response is weakened, but this does not mean that it is not at all.
For example, the brain has “its” immune cells - microglia are isolated macrophages of the brain that protect organ tissues from infectious agents. When phagocytosis ("eating") of the pathogens of infections, microglia produces signals that cause inflammation in certain parts of the brain.
It used to be thought that the presence of the immune system in the brain was limited to microglial cells. But in 2017, Dr. Daniel Reich conducted a series of experiments with his research team using magnetic resonance imaging and identified lymphatic vessels in the meninges of monkeys and humans.
In addition to immune cells and lymphatic vessels, immune molecules also play an important role in the normal functioning of the brain. Thus, the cytokine IFN-γ, a signaling molecule that provides protection against viruses, is involved in the regulation of social behavior.
Scientists from the University of Virginia and Massachusetts Universities have revealed a correlation of cytokine deficiency with social disorders and disturbance of neuronal connections, which were also observed in animals with immunodeficiency. This could be eliminated by introducing interferon into the cerebrospinal fluid.
Myth number 5. If immunity works very actively, then it is always good.
Excessive activity of the immune system can be dangerous for the body. The immune system has the ability to destroy foreign objects, including infectious ones, and rid the body of them. But sometimes the immune system is capable of mistaking harmless body cells for a potential pathogen. As a result of an uncontrolled immune response, allergic or hypersensitivity reactions can occur.
According to the classification proposed by British immunologists Philip Jell and Robin Coombs back in 1963, four types of such reactions are distinguished. The first three types of hypersensitivity reactions are immediate reactions, since the immune response develops several minutes after exposure to an allergen. The fourth type of reaction is characterized by a longer development period - from several hours to several days.
The material was prepared on the basis of the book “How immunity works” by Ekaterina Umnyakova.
The material is published for educational purposes and is not a medical recommendation. ForumDaily Woman is not responsible for the consequences of self-medication and may not share the views of the author or expert.