Vitamin D – Will it help fight Coronavirus? (2)

At this time, probably everyone will be most interested in the effect of vitamin D on the proper functioning of the immune system. "Low levels of vitamin D in the blood have been shown to be associated with an increased risk of viral and bacterial respiratory diseases, asthma and tuberculosis. Vitamin D plays a crucial role in the mechanism of triggering the body's defense and stimulating the immune response," explains MUDr. Petr Podroužek, CSc., Expert director of EUC Laboratoře. The determination that sufficient vitamin D is key to the activation of some populations of white blood cells - T lymphocytes and other components of cellular immunity - was a very important discovery. In the case of vitamin D deficiency, these cellular elements are not able to "be in good shape" and ensure the proper defense of the body, and they are also unable to increase their numbers properly, which is essential for the outcome of the fight against infectious agents. "Studies evaluating data from 11,000 participants from 14 countries in 2017 and others have clearly shown that vitamin D reduces the risk of respiratory infections (mostly caused by bacteria and viruses), increases the levels of microbial peptides - natural substances with antibiotic effects in the lungs.  Its anti-inflammatory effect is also important, " describes MUDr. Podroužek, adding: "The results correlated with the known facts of the occurrence of these infections in the winter and spring months, when vitamin D levels are lowest. Especially in the group with very low vitamin levels, the incidence of respiratory infections after vitamin D supplementation decreased very significantly. "

Therefore, there is a growing circle of experts who attribute winter and spring infections caused by viruses and bacteria to a weakened immune system due to vitamin D deficiency, whose reserves formed on sunny days in the summer have already been depleted and have not been adequately supplemented by vitamin intake from the diet or vitamin supplementation. 

Vitamin D "from the sun" can only be obtained in our Czech conditions during part of the year. From about mid-September to mid-April, due to the low angle of incident rays, the UVB component of solar radiation is absorbed by or reflected from the ozone layer. For possible sunbathing, however, it is always necessary to remember that the incidence of skin tumors has increased in recent years. These are attributed to the effect of direct sunlight on skin which is unprotected, for example by sunscreen. Today, dermatologists say that any dose of ultraviolet radiation puts strain on the skin, so care must be taken.

Dietary supplementation of vitamin D (e.g. sea fish and fish products, egg yolk, milk, cottage cheese, cheese) is generally not sufficient in our conditions. Data from the State Institute of Public Health (SZÚ) show that only 1% of our population is able to supplement vitamin D in this way; a relatively unsatisfactory condition was also found for the pediatric population. In the measurement of more than 400 children (SZÚ 2016), only 14% had optimal vitamin D values in the spring. Therefore, there is a clear need to supplement vitamin D levels with vitamin replacements.

However, the importance of vitamin D supplementation does not seem to be underestimated at this time. In EUC Laboratories, we routinely measure the level of 25-hydroxyvitamin D, one of the forms of vitamin D (with or without a doctor's recommendation for direct payment), in the blood. Compared to the situation two years ago, for example,  today we are much more likely to encounter results of optimal levels of vitamin D. The interest in the examination is quite considerable, with more and more people already paying more attention to their health.

"Respiratory infections are a major cause of morbidity and death worldwide,
even outside the coronavirus pandemic. Vitamin D deficiency increases the likelihood of respiratory disease by impairing immune function.  Vitamin D supplementation is safe and not expensive, so reducing the number of respiratory infections in this form is very effective, "adds MUDr. Podroužek. Although experts warn that the importance of vitamin D in coronavirus (Covid 19) infection has not yet been demonstrated due to the short time required for such a study, it can still be generally assumed that vitamin D could have a positive effect here as well.