If you are looking for a simple and straight-forward answer, the truth is that you really do not need supplements.
If you are looking for an easy and immediate formula to make yourself immune to the coronavirus pandemic, don’t read on. It does not exist.
Trusting the many offers that you will find these days, whether in the form of a vitamin supplement, probiotic, propolis-based or through alternative therapy in a spa, would be unwise.
Right now, the best thing for the immune system is to stay home and be scrupulous with hygienic measures.
But if what you’re interested in is knowing what you can do on a day-to-day basis to keep the defences in an optimal state, go ahead and take note. You will see why it is not as easy as taking a pill.
The first thing to assume – and keep in mind when you are offered easy solutions – is that expressions, like increasing and strengthening defenses, are misleading.
These are concepts that, from a strictly scientific point of view, do not make much sense. It is a very poor argument that understands the immune system as a small and localized entity, with the potential to be easily modified by taking a supplement, for example.
The same happens with abusing the use of supplements. We have a very large number of T cells, which are capable of recognizing thousands of potential invaders, but having more will not do anything if they do not identify the invader.
Strengthening defenses says nothing, and it is precisely the vagueness of its meaning that many people use to sell products whose utility has not been proven.
They may contain nutrients or other substances that have been related to the functioning of the defenses, but from there to reducing the risk of infection is a very different conceptual step. It is even greater if we talk about improving defences.
The immune system does not appear to be susceptible to improvement. If you are one of those people who catch one cold after another you can hope to contract as few as possible, but it is likely that you will continue to be so.
The immune system we are born with is the one we have. Its essence is influenced by a multitude of factors, from genes to past infections, to nutrition, exercise, etc.
We cannot improve it but keep it as close to its original state, with its components in the best possible way for as long as possible. In other words, it is possible to optimize its operation and we can do some things to achieve it.
It is in our hands to maintain it in the best conditions with a healthy diet, doing adequate exercise and sleeping as necessary. It is also a great idea to keep stress at bay. It is not as comfortable as going down to the pharmacy, but it works.
Exercise your defences
The human body has an important catalogue of resources to stop invasions. The first barrier is the skin, which in addition to marking a physical border, has microbiota that will fight so that any microbe does not take away its territory.
Respiratory viruses do not penetrate through it, but through the mucous membranes, which form the border in the body cavities communicated with the outside.
They are those that are inside the nose and mouth, for example, and through which pathogens such as the new coronavirus enter.
The organism also has chemical resources such as lysozyme from saliva, an enzyme that destroys the structures of some pathogens; and the acidic pH of the stomach, a hostile environment for both pathogens and probiotics that some companies offer as allies of the immune system.
It is true that the intestinal microbiota has defensive functions, which are based on the fact that the microbes settled in the digestive tract are reluctant for other microorganisms to occupy their space. But influencing them is very complicated.
One of the first problems we have is that a probiotic that we take by mouth passes the gastric barrier, due to the large changes in pH that occur.
The last frontier of the immune system is made up of “soldiers.” A vast array of biological entities such as macrophages and dendritic cells, dedicated to capturing invaders and breaking them into pieces called antigens.
With them, the template is made on which the B lymphocytes work to generate antibodies. Studies have been published that conclude that physical exercise improves the antimicrobial capacity of cells such as macrophages, which slows down the ageing process influencing immunosenescence, which refers to the loss of capacity of the immune system as a result of age; and that it affects a fine balance between inflammation and anti-inflammation, which is very interesting because among the diseases associated with inflammation are some as important as cancer.
According to some works, a session of less than 60 minutes of aerobic exercise, of moderate to vigorous intensity, not only increases the antimicrobial capacity of macrophages, but physical activity also mobilizes a flood of cells involved in the immune response: Changes in blood circulation cause soldiers to reach more tissues, increasing the intensity of their vigilance and action.
Studies have also been published that indicate that physical exercise reduces the concentration of stress hormones such as cortisol, and anyone who has been stressed for long periods of time has been able to verify that there is a relationship with infections such as those that cause colds.
It seems that a short-term stress level, lasting between a few minutes and a few hours, is positive for the immune system, but when it is chronic it has adverse effects, says the researcher.
This is due, in part, to the effects of hormones whose production is altered in stressful situations such as the aforementioned cortisol and epinephrine.
The role of long-term stress on the immune system is another huge unknown, but there are studies that point out some effects.
It has been shown that it is detrimental in the development of tumors by reducing the way in which they are ‘recognized’, it has been observed that it increases autoimmune pathologies, although surely this is due to a set of many factors that stress can trigger, and it has been related to a decrease in the fight against pathogens.
The same goes for sleep. Scientists have long suggested that you generally need to sleep 7 to 8 hours a day to maintain a proper immune system. But it is not known why sleeping poorly is harmful.
It has been said, for example, that doing it less or more than the recommended hours is associated with an increase in inflammation markers in the body, including that sleeping too little is associated with a higher production of a cell type behind the development of arteriosclerosis plaques, responsible for coronary events such as heart attacks and strokes.
The latter again highlights that more is not synonymous with better.
So what are supplements good for?
Scientific studies link a wide range of nutrients with the functioning of the immune system, a set of minerals and vitamins that are commonly sold in supplements.
But they are useless for the vast majority of the healthy adult population because regular food is enough for them, as long as the food itself is nutritious.
There are some nutrients such as copper, folates, iron, selenium, zinc, vitamins A, B12, B6, C and D that contribute to the normal functioning of the immune system, but the European Food Safety Authority says its consumption is unlikely to be associated with an increase in defences and a lower risk of getting any infection
The body is not going to absorb more at the intestinal level than it needs. Many of these substances, if they are not really needed, will be eliminated by the body.
The benefit in the immune system is obtained by taking a varied diet based on nutritionally dense fruits, vegetables, legumes, whole products, nuts and fermented dairy. Both probiotics and prebiotics can have benefits in intestinal health apart from the immune ones.
The use of supplements should be reserved for those who have a deficit or deficiency state, such as vitamin D deficiency, which affects a large part of the population, and for the elderly who have any pathology that may influence the immune system.
The most important thing is not to fall into the trap of creating an association between this type of product or the lifestyle and infections such as the one that caused the pandemic of coronavirus.