In order to react faster to recurring threats, the acquired immune defense exists. The immune defence acquired throughout life reacts selectively from pathogen to pathogen, the defence system also remembers them and reacts faster and more effectively at the next contact. The immunological memory develops.

Unfortunately, our innate immune system does not recognize some pathogens such as viruses or bacteria. These can therefore cause damage in the body. Now the so-called dendritic cells come into play: They also eliminate unknown pathogens and destroy them. Particles of the pathogen shell are transmitted to T cells. These special cells know almost every pathogen. The T cells multiply immediately and fight against the pathogen. T cells in turn activate the B cells. These form exactly the right defense substances against a certain type of pathogen - the so-called antibodies. These antibodies bond to the respective pathogen and mark it so that it can be destroyed more quickly by the scavenger cells.

The remarkable: B-cells remember the nature of the pathogens. If the infection reoccurs, the body can quickly produce the appropriate antibodies and defend itself.

Pathogens are constantly entering our body. Almost all of them are eliminated by our immune system without us noticing. This is where, for example, the skin cells come into play, which represent an external barrier against intruders and constitute the first protective barrier. With a surface area of almost two square meters, it constitutes an important and strong barrier in combination with the mucous membranes of the mouth, throat, nose and gastrointestinal tract. With an incredible eight meters in length and 500 square meters of surface area, our intestine is the largest immune organ in the body and as large as a soccer field!

Patrolling scavenger cells, so-called macrophages, recognize the intruders on their surface, devour them and decompose them inside. In addition, they use messenger substances to summon further defence cells, like the so-called granulocytes. These destroy the remaining pathogens with the help of substances.

Granulocytes fend off harmful bacteria, parasites and worms. Monocytes are scavenger cells, they break down harmful cells. Lymphocytes recognize pathogens such as viruses and produce antibodies against them.

An unbalanced diet can negatively affect the immune system. Malnutrition or poor nutrition can impair the immune response. However, there are many different aspects to be considered, from sufficient vitamins up to sufficient secondary plant nutrients. For example, it has been found that a deficiency of individual amino acids can lead to a deterioration in immune function. This is because amino acids influence, among other things, the activation of many immune cells and are needed for the production of antibodies. It is therefore important to pay attention to a balanced diet and ensure that the body has all the necessary nutrients at its disposal for an optimally functioning immune system.

Our immune system consists among other things of a large variety of blood cells, or also white blood cells, the leukocytes. These cells make up a large part of our immune system and are produced in the bone marrow. The primary task of leukocytes is the defense against pathogens. When these cells don't work properly, it affects our entire immune system. It is therefore important to strengthen the cells in our immune system.

Restorative sleep supports our immune system. That seems to be common knowledge. Initial studies have looked into the question of why this is and found that our T-cells, which normally have the task of fighting pathogens such as viruses or bacteria, are less able to bond when there is a lack of sleep. This decreased function could be demonstrated even after three hours without sleep. Therefore always listen to your own body and make sure that it gets enough restorative sleep.

When we suffer from constant stress, our immune system also suffers. This is because both the innate and the acquired defenses suffer from this stress. Because if we feel permanently overwhelmed at work or at home, this leads to a decreasing number of immune cells in our blood. The natural killer cells are also less active and the T lymphocytes multiply more slowly. Therefore it is important to avoid long lasting stress and to find a balance in everyday life, so that our immune system can work completely functional.

When you do physical activity your body releases adrenaline. This ensures that the immune cells multiply faster and become more active. Not only our natural killer cells and white blood cells, but also the T and B lymphocytes are increased in the bloodstream. If you then stop exercising (and the adrenaline in the blood goes down), the number of immune cells in the bloodstream also goes down again. These repetitive, small stimuli during regular exercise train the immune system, which results in the lymphocytes being more active and harmful cells are eliminated faster and better. Therefore, compensating exercise helps to strengthen our immune system.

Few people doubt that there is a connection between body and mind. One of the best known examples is the placebo effect. Here the mere belief in taking a curative drug leads to an actual recovery. But how the mind influences our immune system has not been known in detail for a long time. However, initial research now indicates that the happiness hormone dopamine activates certain parts of our immune system. When the brain releases a larger amount of this hormone (for example, when we feel happy) there are significantly more scavenger cells in the body. Not only that, the number of antibodies in the bloodstream also increases noticeably. Thus, positive thoughts & emotions seem to have a positive effect on our immune system.