Immunity is our protective shield. Activate it the right way not only in the fight against the coronavirus (2)

How immunity works

The immune system is composed of many different types of cells, tissues and substances whose mutual synergy plays a key role in the human body’s resistance to disease. Thanks to these cells, tissues and substances, the body is able to fight off foreign agents – bacteria, viruses, mould, fungi and their toxins. However, risks also lurk within the body, so the immune system’s task is also to eliminate the body’s own potentially harmful cells (for example, old, damaged or cancerous cells).

The immune system comprises two parts: innate and acquired immunity. Innate (non-specific) immunity consists of white blood cells, as well as skin and mucous membranes. White blood cells are able to absorb foreign agents (antigens) and render them harmless in a matter of minutes, though only if they are definitively convinced that the given agent is really an antigen. However, they are note able to remember the foreign agent for the next time. Conversely, acquired (specific) immunity consists specifically of white blood cells maturing in the thymus and bone marrow (T and B lymphocytes). These are able to remember the antigen and respond immediately upon the next encounter with it.

Innate and acquired immunity must work together in the fight against the coronavirus

SARS – CoV2 (COVID-19) is a completely new type of virus for our immune system. Because it spreads rapidly in the population, our innate immunity is not able to immediately respond to it. It has to undergo a relatively long process until acquired immunity can deal with it and remember it.

Unlike bacteria, the virus first attacks the cell directly. Innate immunity responds to the attack with a number of cells, so-called natural killers (NK cells), and other innate immune cells (dendritic cells) recognise the virus with their receptors, absorb it and destroy it. Parts of the virus cell then confer specific immunity to the cells, which trigger reactions eliminating the virus. It is only at this stage that specific antibodies are formed and subsequently circulate in the blood and ensure immunological memory.

 Weakened immunity increases the risk of infection; seniors and obese people are at greater risk 

People with weakened immunity are among the groups most at risk of COVID-19 infection. These people include seniors, as our immunity weakens as we grow older. Among other things, this is due to the declining production of immune cells in bone marrow, reduced production of antibodies on the mucous membranes and impaired function of the immune system as a whole. The course of the disease is thus usually more severe in seniors due to the body’s increased inflammatory response.

“Obesity also has a negative impact on the immune system. It causes a partial loss of the immune ability (impaired activity of the white blood cells, reduced production of antibodies). At the same time, the course of the disease tends to be more severe in obese people, because fatty tissue is a source of pro-inflammatory agents that cause a state of chronic inflammation in the body even before infection occurs,” says Ing. Mgr. Jitka Jirků, nutritional therapist at Canadian Medical.

We can strengthen our immunity with proper diet

Currently, one of the key measures thus comprises restriction of the spread of the disease and rapid development of vaccines. Therefore, there is an intense need to strengthen our immunity, which can be achieved though sufficient rest, physical activity (ideally in fresh air) and by eating the right foods.

“Our immune system is always active. It never rests and in the course of an infection, it is much more active and more demanding on resources (the metabolism speeds up, there is an increased need for substances for forming new cells, etc.), which it must get from our diet,” explains Ing. Mgr. Jitka Jirků. Sufficient amounts of vitamins and trace elements play a key role in the proper functioning of the immune system with respect to both prevention and treatment of disease. Healthy gut flora (intestinal bacteria) is an integral part of an optimally functioning immune system.

Key vitamins in the fight against infection include A, C and D, which are directly responsible for the maturation and effectiveness of immune cells, including their ability to distinguish harmful agents, and the effectiveness of their response. Vitamins B6, B12 and folate are important for the activity of white blood cells. Our diet must also include the antioxidant vitamins C and E, as well as antioxidant enzymes, which contain selenium, zinc, copper and iron. These protect the body against oxidative stress and are thus an integral part of our immunity. A sufficient amount of plant-based foods, fibre and fermented foods is important for the growth and support of healthy gut flora. This clearly requires regular and sufficient consumption of fruits, vegetables, wholegrain products, nuts, eggs, fish and dairy products (ideally fermented). Another indispensable part of one’s diet is omega 3 fatty acids, which are found in high-fat fish and have an anti-inflammatory effect. Their variability helps to achieve optimum intake at times when the body places increased demands on all immune functions.

Why should you know your level of vitamin D?

“Vitamin D is of fundamental importance for human health. A lack of it has an unfavourable impact on immunity – for example, in the case of respiratory-tract illnesses, heart and muscle function, blood pressure, the nervous system, healthy development of bones and teeth, and the risk of occurrence of certain types of cancer,” says MUDr. Petr Podroužek, CSc., specialist director of EUC Laboratories.

In winter and spring, we do not get vitamin D from sunlight (the UVB component of solar radiation is missing) and we thus have to get it from food or vitamin supplements. Experts point out the absolutely deficient level of vitamin D diagnosed in more than 40% of the European population over the course of the year.

You can easily find out what level of vitamin D you have in your body. “The examination is done in the form of a blood test. It is necessary to have an empty stomach when you give a sample, so you shouldn’t eat or smoke for approximately 12 hours beforehand. It’s good to drink a quarter-litre of water or unsweetened tea before having blood drawn,” MUDr. Podroužek advises.

It is also currently possible to use a test that is now offered in the form of a discounted bundle, with which you can find out not only your vitamin D level, but also your level of COVID-19 antibodies. You can get the test at EUC Laboratories collection points throughout the Czech Republic.