Probiotics can be beneficial in helping to keep you from getting sick. They are live bacteria and yeasts that are naturally found in some foods or can be taken as a dietary supplement. Probiotics help balance the good and bad bacteria in your gut, which supports a strong immune system. Studies have shown that probiotics may help reduce colds, the duration of illnesses, and gastrointestinal distress. Additionally, probiotics may help boost immunity by increasing the production of antibodies, which fight off infection. While more research is needed to confirm these effects, it’s possible that probiotics could play a role in keeping you healthy by providing additional defense against illness-causing germs. Let’s find out more about probiotics – how probiotics improve immune system.
Probiotics and immunity
More and more often you can meet the statement that a large part of the human body’s immunity is hidden in the intestines. This may be a kind of generalization, but is it true? Not necessarily.
The main task of the immune system is to protect the body against biological agents, such as bacteria, viruses or fungi, which contribute to the development of a number of diseases. It also provides a form of barrier against harmful chemicals and physical damage.
Proper immunity depends, of course, on the efficient operation of the entire immune system and all its components, but the intestines are a kind of treasury of microbes that are able to support the operation of this complex system.
The aforementioned treasury of microbes is the microbiota , i.e. the totality of microorganisms, both beneficial and pathogenic, that inhabit the host’s body. It is estimated that the weight of the entire microbiota colonizing the human mucous membranes may weigh up to 2 kg. The number of cells in the microbiome , i.e. the collective genome of microbes represented by the microbiota, is ten times greater than the sum of all cells in the human body.
The microbiota includes primarily bacteria, but also viruses, fungi, protozoa and flatworms. Diverse groups of microorganisms are located in different areas of the body, e.g. on the skin, in the respiratory, genitourinary or digestive tracts. The largest concentration of microbiota is in the intestines.
Testing results on intestinal microbiota
The intestinal microbiota is not only the most numerous, but also the most diverse, active and, what is extremely important, studied. Although testing 100 trillion microorganisms inhabiting the intestines is not easy and possible at the moment, scientists have managed to effectively analyze a significant part of microorganisms, isolate the beneficial ones and indicate their properties.
It is the specific properties of the microbiota, its composition and balance, that have gained fundamental importance for the health and proper functioning of the human body.
It has been proven that the correct intestinal microbiota performs a number of important functions, ranging from metabolic, through supporting, to protective.
In this case, supporting immunity by beneficial microorganisms consists primarily in protecting the body against the multiplication and negative effects of pathogens and by stimulating the cells of the immune system.
Therefore, it is worth taking care to keep any bacteria, viruses or fungi living in the intestines in a state of eubiosis , i.e. quantitative and qualitative balance. This is because it affects the homeostasis of the entire body, including defense functions.
It is assumed that the level of beneficial microorganisms should definitely prevail over harmful ones, approximately 85 percent. up to 15 percent It is not difficult to guess that if this advantage starts to decrease , intestinal dysbiosis may occur , and thus the development of many diseases, not only in the area of the digestive system, but also the immune system.
So it is directly related to a possible decrease in immunity. How can the intestinal microbiota be supported in such a situation? Mainly through a properly balanced diet, a healthy lifestyle and providing the body with the right dose of specific probiotics , commonly known as “good bacteria”.
What are probiotics for immunity?
Over the years, beneficial microbes have been given numerous definitions. According to the current one, proposed by WHO and FAO (Food and Agriculture Organization of the United Nations), probiotics are live, strictly defined strains of microorganisms contained in special products or preparations, which, when administered in sufficient doses, affect the microbiota of a given area of the body, thanks to which they have a beneficial effect on health.
For a microorganism to be considered a probiotic , it must meet certain criteria. It should primarily:
- come from the human microbiome
- maintain complete safety towards the human body
- show resistance to low pH of gastric juice, pancreatic enzymes and bile
- have the ability to adhere, i.e. adhere to intestinal epithelial cells
- act antagonistically against pathogens
- prevent pathogenic microorganisms from entering the intestinal walls
- maintain vitality and efficiency for rapid cell multiplication during intestinal transit and easily colonize the intestine
- be resistant to antibiotics
- produce antimicrobial substances and fight pathogenic microorganisms
Probiotics include mainly properly selected beneficial bacterial and yeast cultures. These are primarily strains of bacteria Lactobacillus, Bifidobacterium, Enterococcus faecium, Lactococcus lactis, Streptococcus thermophilus and the yeast Saccharomyces boulardii.
They can be found in some food products and probiotic preparations, including probiotic drugs, probiotic dietary supplements, dietary foods for special medical purposes, and functional foods.
How do probiotics work for immunity?
Probiotics for immunity are introduced into the body intentionally, usually orally. Probiotic microorganisms must travel through all sections of the digestive tract and reach the intestines in a living form.
There, they trigger different mechanisms of action, both immunological and non-immune. The effect of probiotics on immunity is based primarily on:
- penetrating the body and adhering to the intestinal walls, which is a protective barrier against pathogenic microorganisms
- maintaining the proper pH in the intestines or acidifying it, which prevents the development of pathogens
- production of lactic acid, hydrogen peroxide and bacteriocin, which allows the elimination of pathogenic bacteria
- activation of immune receptors that stimulate the immune system to work, thanks to which the number of antibodies increases and the synthesis of cytokines (proteins that stimulate or inhibit the immune system) is induced
- stimulating the enzymatic and phagocytic activity of macrophages and granulocytes, i.e. cells of the immune system
- increasing the number and activation of natural killer (NK) cells, i.e. cytotoxic immune cells, responsible for the elimination of cancer cells or cells infected by viruses or bacteria
- competing for receptors or adhering to epithelial cells, thus blocking pathogens and allergens from accessing the intestinal epithelium
- competition with other microorganisms for nutrients
- destroying free radicals
- supporting the proper absorption of vitamins and nutrients
In their immunomodulatory effect, probiotics stimulate and control natural immune mechanisms directed against pathogens of bacterial, viral and cancer origin. They also contribute to the inhibition of aggressive and allergic reactions.
Before buying a specific probiotic for strengthening, you must read the label or information leaflet. The value of a given probiotic is also determined by:
- proper classification of genus, species and strain
- comprehensive characteristics of the strain
- precise indications for use
- recommended dosage
- determination of the number of viable colonies of microorganisms in CFU units (preferably around 15-20 billion)
- expiration date
Probiotics in a diet
Taking care of the proper functioning of the immune system, one should not forget about a proper diet, to which it is worth introducing natural probiotics for immunity. Among the probiotic food products, we can mention primarily yoghurts, kefir, buttermilk, curds, unpasteurized cheeses and all kinds of pickles, including sauerkraut and pickled cucumbers. Lovers of more oriental flavors can reach for kombucha, kimchi or natto.