It is circulating on the Internet that you can protect yourself against corona with vitamin D agents. That sounds tempting – but according to a new study that has been praised for its methodology, it is not.
New York (AP) – According to a new US study, a low vitamin D status is not a risk factor for infection with the coronavirus.
Although there seems to be such a connection if you look at the data alone, the researchers explain in the specialist magazine “Jama Open Network”. But if you include influencing factors such as age, gender, ethnicity, body mass index, blood pressure, smoking status and place of residence, there is no connection whatsoever. People with a comparatively low vitamin D level therefore do not have a higher risk of contracting Sars-CoV-2 than people who are optimally supplied with the vitamin.
The scientists led by Yonghong Li from the US laboratory company Quest Diagnostics in San Juan Capistrano (US state California) had analyzed data from the employee health program with annual screenings from 2019 and 2020. A total of 18 148 people between the ages of 37 and 56 were included, around two thirds of them women. Before the pandemic began, around 60 percent of those examined had a vitamin D level of less than 30 nanograms per milliliter (ng / ml), and around 25 percent even lower (less than 20 ng / ml).
Antibodies against Sars-CoV-2 were detected in around five percent of the test subjects (900) during the study period. It is true that the employees and relatives who tested positive had, on average, a lower vitamin D level than those who tested negative. Taking into account other factors that noticeably influence the corona risks, however, there was no significant correlation. For example, clearly overweight people (BMI from 30), men and women with high blood pressure, smokers and employees and their partners without a university degree were more likely to have a vitamin D deficiency on average.
Other, smaller studies had previously indicated a possible connection, but in many cases the many factors that influence the corona risk were not taken into account. In addition, the vitamin status was often measured either a long time beforehand or only in the course of the Covid 19 disease – so that, according to experts, it cannot be deduced from the measured value whether a measured deficiency was not only due to the infection.
According to the authors, one of the limitations of the new analysis is that not all corona infections can be detected using antibodies – among other things because they disappear after a certain time. The study does not make a statement about the severity of Covid 19 diseases depending on the vitamin D status. In a comment on the study in “Jama Open Network”, US health expert Michael Polis praised the methodology of the analysis. “This study shows that a well-designed, appropriately sized observational study can provide more definitive evidence than several smaller, poorly-designed studies.”
Vitamin D is the generic term for a group of fat-soluble vitamins. Unlike other vitamins, the body can produce vitamin D itself – through sunlight, more precisely UV-B radiation of certain wavelengths. However, recommendations for the intake of vitamin D preparations have been making the rounds on the Internet for a long time – currently often based on information that this could prevent an infection with the coronavirus or a severe course of Covid 19 disease.
So far there is no scientifically proven evidence for this and authorities such as the Federal Institute for Risk Assessment (BfR) repeatedly warn of the health risks of independent intake, especially of higher-dose vitamin D preparations. If the vitamin D level in the body is constantly too high, there is a risk of damage to health such as the formation of kidney stones or calcification of the kidneys.
A good supply of vitamin D can best be achieved through the skin’s own synthesis, according to the BfR. In addition, it is recommended to eat fatty sea fish such as herring or salmon once or twice a week. A general vitamin D intake of up to 20 micrograms per day should therefore only be considered for people such as nursing home residents who rarely exercise outdoors.
In general, a sufficient supply of vitamins and minerals is important for human immune function, according to the BfR. To protect against colds and respiratory diseases, a varied diet with lots of fruit and vegetables rich in vitamins and minerals is therefore generally important.
© dpa-infocom, dpa: 210521-99-685089 / 3
