The coronavirus currently occupies the entire world and determines the everyday life of countless people. Shops are closing, curfews are being imposed, whole cities and sometimes even whole countries are being sealed off.
In addition to many other scientific disciplines, nutritional science is also dealing with the topic of the coronavirus and is investigating the importance of nutrition in protecting against viral infections.
Common effective public health strategies that can contain the spread and impact of virus-related respiratory diseases, which are now being preached to us daily by the media, include washing hands, avoiding contact with infected persons and coughing and sneezing into the crook of your arm (1). In addition, for certain viral diseases, there is the possibility of protecting oneself from them by annual vaccination. In discussions about immunity and protection against infection, nutritional strategies to support optimal immune function are often only neglected, although it is already well known that nutrition plays an important role in the functioning of the immune system (2).
Now, of course, the question arises as to how we can protect ourselves to a certain degree against viral infections through our diet, and thus also currently against Covid-19. It has been scientifically proven that vitamins A, B6, B12, C, D, E and folate, among others, and the trace elements zinc, iron, selenium, magnesium and copper play an important role in supporting our immune system. In addition, especially the long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) protect against inflammation and thus help the immune system to concentrate fully on external pathogens (2).
It is also clear that nutrient deficiencies or low nutrient storage levels have a negative effect on immune function and lead to increased susceptibility to infections (3, 4).
Obviously, a whole range of nutrients are involved in optimal immune function.
An ideal supply of all these nutrients can be achieved through a balanced and varied diet (2) based on a predominantly (5) or (under certain conditions) exclusively plant-based diet (in this context-it means vegan) (6).
However, the supply status of the average European population shows that very few people practice such a diet. In particular, the nutritional requirements of vitamin D, vitamin E, vitamin C, folate and selenium are hardly met in Europe (7). Especially in older groups it can be observed that the supply of vitamin C (8), vitamin D (9) and/or vitamin B12 (10) is insufficient. This could be an explanation why this age group in particular has a weakened immune system and is at particularly high risk of new types of infection without adequate vaccination.
This poor supply status can be traced back to a very one-sided diet of the general population. According to the National Consumption Study II (NVS II), adults in Germany (but the numbers are pretty accurate for the U.S. too) consume too much meat, meat products and sausages on average, while the guideline values for the consumption of vegetables and fruit are not reached (11).
There is therefore a lot of upward air. An overview of nutrients and their occurrence in plant foods is shown on the website of ProVeg International. For the triad of ethics, ecology and health, we recommend the combination of different types of fruit and vegetables, legumes, whole grain cereal products and nuts or seeds.
For the sake of completeness, it should be mentioned that, purely from a health point of view, even small amounts of animal products can be consumed in order to supply certain nutrients such as vitamin B12. However, these are only used as a little addition to a whole food plant-based diet and are not recommended by us from an ecological and ethical point of view.
An overview of the recommendations for a balanced mixed diet (including animal products) is available from the Dietary Guidelines for Americans.
So stay healthy and #stayathome !
2. Calder, P.C.; Carr, A.C.; Gombart, A.F.; Eggersdorfer, M. (2020): Optimal Nutritional Status for a Well-Functioning Immune System is an Important Factor to Protect Against Viral Infections. Preprints 2020, 2020030199
11. MRI (Max-Rubner-Institut, Bundesforschungsinstitut für Ernährung und Lebensmittel) (Hrsg.) (2008): Nationale Verzehrsstudie II. Ergebnisbericht Teil II. Die bundesweite Befragung zur Ernährung von Jugendlichen und Erwachsenen. Karlsruhe