Have you always wondered how our body actually manages to defy all the external influences in daily life? We have contact with other people, move through the public and touch objects that have touched millions of people before us. At least as many bacteria end up on our hands and ultimately in our very own biological system, the body. Apart from the fact that our body itself contains an incredible amount of bacteria, without which, for example, the gastrointestinal system could not function properly at all, there are many external influences that affect it.
All these influences are classified into good and bad and the body reacts accordingly. The only instance that really decides who is considered an enemy and who is considered a friend is the immune system. It acts like the bouncer for all molecules that want to come in and find a home. It acts in parallel in many parts of the body and normally functions very reliably. Even if pests, such as bad bacteria or viruses, have spread in the body, the immune system intervenes to get rid of them by fever and other biological tricks.
In this guide you will learn more about what the immune system actually is, how it works and what you can personally do to make it stronger and build it up. In addition to many tips for everyday life, you will also learn about aspects of nutrition. The following tips to try out for yourself will give you an insight into a healthy diet that provides your body with enough nutrients so that your immune system also performs at its best.
What is the immune system?
The immune system is basically a term for the body's defence system that keeps pathogens away. This mechanism is intended to prevent the corresponding pathogens, which initially only enter the bloodstream in their specific form, from causing physical changes such as tissue damage to and in the body.
The tasks of the immune system cover all sources of danger that lurk outside and inside the body. This includes the removal of any microorganisms that have entered from outside and do not belong in the body's own environment. In addition, foreign substances as well as body cells that have a faulty effect on the immune system are rendered harmless.
Whoever thinks that the immune system is a very specific area in our body is unfortunately mistaken. This complex network includes different cell types, molecules and organs, which all together even occupy their own field of research.
Because the immune system protects the human organism from external dangers, it is just as important for survival as each of our individual organs. Harmful external threats that penetrate the body and are completely ignored cause illness and dysfunction.
You will probably be familiar with most pathogens. These include viruses, bacteria, fungi and multicellular parasites. If there is no external threat, the body itself is such a complex mechanism that even within rare cases, sources of error can lurk.
No cell in our body lives forever and is renewed over time. When these cells have fulfilled their function and are detached, they normally die and are broken down by the body. Unfortunately, it can also happen that exactly these cells undergo pathological changes and, for example, grow unchecked. This well-known example is called cancer. To be able to protect itself in such cases, the body has an innate immune response. In addition to this, the evolution of vertebrates from the beginning of their development also developed an adaptive immune defence system that protects even more effectively.
The unspecific or innate immune defence
The innate immune defence, which can be found very early in the tribal history, concentrates mainly on a construction of the body and the organs, which is as effectively as possible armed against external negative influences and, as the name suggests, is active from birth. This immune defence includes anatomical barriers such as epithelia, through which not every substance can get in and out unhindered.
It also includes phagocytosis, which is responsible for the active absorption of selected particles. Inflammation, which is also a part of phagocytosis, embodies a physical reaction to foreign bodies noticed in tissue.
Finally, the complement system also belongs to the innate immune defence. The complement system comprises more than 30 proteins that humans carry within themselves. These are located in the blood plasma and fend off or even destroy pathogens. All these components of the immune response take place within a few minutes and are determined in advance by the genetic information.
They cannot therefore be changed.
The specific or adaptive immune defence
The so-called acquired immune system, as the name suggests, develops retrospectively and essentially arises from the already innate immune defence.
It embodies the ability of living beings to adapt to new pathogens and external influences and thus to act effectively on an ongoing basis. The specific immune defence consists of cells that form a kind of operational basis. These cells are able to recognise harmful molecules, to form specific defence mechanisms on a cellular basis and even to produce antibodies.
In this immune defence there are essentially two different elements that interlock like cogs. The T-lymphocytes ensure the immune response, i.e. the guaranteed reaction to foreign substances in the body. These have a supporting effect on the second group, the B-lymphocytes. This group is specifically responsible for combating harmful influences in all body fluids. They develop antibodies which then act directly in the body fluids and destroy the pests.
Once both components have developed as a specific response to a particular pathogen and successfully banished it from the body, most of the developed cells are broken down again. However, some of the new antibodies and memory cells for this specific immune response remain. This should ensure that renewed contact with the same pathogen is faster and more effective. The body is then, so to speak, immune to precisely this intruder.
It is particularly important to realise that the innate immune defence cannot do without the adaptive one and vice versa. An effective immune system is only guaranteed by the interaction of these two.
Components of the immune system
Biochemical and mechanical barriers
The very first lines of defence against all pathogens are the biochemical and mechanical barriers of the body. These have the essential function of preventing pathogens from entering the body in the first place and, if they are already in the body, of expelling them as quickly as possible.
The skin is the very first layer. It has its own milieu consisting of sweat, sebum and an ever-present flora of good bacteria. The combination of all of these is intended to make growth impossible or at least limit it for outside microorganisms.
All mucous membranes bind the mucus and thus make micro-organisms more immobile. The eyes are supported in their fight by the enzyme lysozyme and transport any molecules away with the tear fluid. The respiratory tract also binds the mucus and transports everything undesirable away with the help of the existing cilia. The oral cavity has a similar combat structure to the eye. The enzyme lysozyme also supports the destruction of pathogens in saliva.
The stomach is characterised above all by the gastric acid, which is very effective due to the hydrochloric acid it contains in combination with enzymes that can break down protein. This combination is able to destroy almost all invading microorganisms or bacteria.
The intestine is mainly responsible for the regular removal of the pests. The intestinal flora also functions as a defence against infections. The urinary tract functions similarly to the intestine by permanently emptying it and makes use of the concentration of urine.