Immunity in autumn and winter – which dietary supplements are worth taking to boost it?

As every year, with the onset of autumn in Poland, the season for colds and flu begins. However, dietary supplements for immunity, which can be purchased without a prescription, come to the rescue. That is why in the following article you will find information about what the immune system is, how it works and what weakens it. In addition, you will learn which vitamins and preparations are worth taking to strengthen your immunity.

Immunity and the immune system – what are they?

Simply put, immunity is the body's ability to fight colds caused by pathogens and microorganisms. What is more, there are two types of immunity. These are:

• Innate immunity – the first line of defence in the fight against germs.
• Acquired immunity – immunity that develops over time. It works in such a way that, as a result of contact with a microorganism, the immune system remembers it, which leads to the development of so-called immunological memory. Thanks to this, the next time the body comes into contact with the same germs, it knows how to deal with them.

The immune system, also known as the immunological system, is a system whose functioning involves the so-called primary and secondary lymphatic organs. The former are responsible, among other things, for the development of lymphocytes and include the thymus. Interestingly, this organ disappears with age. The latter, i.e. secondary lymphatic organs, include lymph nodes, tonsils, spleen, lymphatic tissue of the digestive tract, etc. It is in these organs that pathological changes caused by microorganisms occur. It is also worth mentioning that types of immunity can be divided into non-specific passive and active, as well as specific passive, active and cellular.

What weakens immunity?

Unfortunately, a characteristic feature of immunity is that it weakens as a result of contact with germs and pathogens. In practice, this means that the body becomes susceptible to diseases and colds. What is more, immunity can also be weakened by adverse factors, both external and internal. These include factors such as:

• Age,
• Gender,
• Genetic conditions,
• Poor diet,
• Lack of physical activity,
• Excessive stress.

Therefore, people who are exposed to high levels of stress, eat unhealthily and, in addition, do not engage in any physical activity, are at the highest risk.

Immunity in children and adults

When talking about immunity in children and adults, it should be noted that it differs in several respects. This is because each of us is born with specific, or innate, immunity, which is acquired in the womb. Genetically determined, it develops in children during the first months of life. Furthermore, it does not require activation, as is the case with acquired immunity, which begins to develop from around 3 months of age and continues to develop throughout our lives. The difference between them is that in the early stages of their lives, children acquire immunity through their mother's body (during the prenatal period) and, after birth, through their skin and mucous membranes, among other things. Factors such as the following therefore influence the development of innate immunity in newborns:

• Excessively low pH of the skin and mucous membranes of the digestive system,
• Production of lactic acid, which is produced in the intestines by probiotic bacteria,
• Cationic proteins that break down the cell walls of bacteria, enveloped viruses and parasites.

In adults, on the other hand, acquired immunity plays a much more important role. This is not inherited, but acquired with age. In order for it to develop, prior contact with the pathogen is necessary, as this causes the body to become immune. Thanks to this, when our body comes into contact with these germs again, it immediately begins to fight them, which reduces the risk of illness. What is more, it is under the influence of these pathogens that monocytes are produced in the bone marrow, T lymphocytes in the thymus and B lymphocytes in the spleen and lymph nodes.

Immunity supplements

Fortunately, immunity can also be built up with the help of vitamins and supplements that can be purchased without a prescription. It is important that they contain nutrients that support the immune system – both at the level of the physical barrier, cellular immunity and antibody production. More information on this is provided below.

Vitamin C

Also known as ascorbic acid, vitamin C is a very powerful antioxidant. This means that it has antioxidant properties and destroys free oxygen radicals, which cause cell degradation, including immune system cells. Regular supplementation with vitamin C increases the activity of macrophages and granulocytes, which protect cells from oxidative stress. When taken during illness, it effectively shortens the duration of infection, and when taken daily, it strengthens and seals blood vessels, keeps connective tissue in good condition, accelerates wound healing and promotes iron absorption.

Vitamin D

Another important supplement for immunity that is available without a prescription is vitamin D. The chemical compounds it contains have a beneficial effect on immune cells. Interestingly, many of them have vitamin D receptors on their surface that absorb it. It is also worth mentioning that vitamin D affects the transcription of immune cell genes and weakens and helps prevent inflammation.

Zinc

Zinc, which is essential for the proper functioning of our body, also helps to strengthen immunity. What is more, it accelerates the absorption of certain vitamins and has an antioxidant effect, protecting us from free radicals. This element also supports our immunity, and its deficiency increases the risk of frequent infections, colds and other diseases. It also has immunomodulatory properties, which means that zinc is involved in the proper maturation of immune system cells, including T lymphocytes, phagocytes and many others.

Omega-3 and omega-6 fatty acids

Next on our list are unsaturated fatty acids, which, among other things, have a cardioprotective effect and support prenatal development. Therefore, they should be taken by pregnant women in particular. Otherwise, it may affect the child's innate immunity. Omega acid supplementation also helps to strengthen the immune system and stimulate it to fight microorganisms. They also have a strong anti-inflammatory effect, which effectively reduces pro-inflammatory markers.

Probiotics

Last on our list of dietary supplements for immunity are probiotics, which stimulate the bacterial flora in the intestines to fight bacteria. In addition, some strains of bacteria are capable of producing toxins that are lethal to bacteria. Others, in turn, can alter the pH, which prevents microorganisms from colonising the digestive tract and, as a result, protects against the development of colds. Probiotics also have an immunomodulatory effect, which means that they maintain immune tolerance to environmental antigens, control the body's immune response to pathogens, and inhibit allergic and autoaggressive reactions.

How to strengthen immunity?

Weakened immunity is a natural phenomenon, especially in the autumn and winter. Fortunately, dietary supplements for immunity, which can be purchased in pharmacies without a prescription, come to the rescue. When choosing such a supplement, however, it is worth remembering to look at its composition. The most effective supplements contain vitamin C, D, zinc, probiotics, and omega-3 and omega-6 fatty acids. If these ingredients are listed in the product's composition, you can be sure that these preparations will help strengthen your immune system.

Bibliography

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