Unfortunately most critical cases of Covid-19 are seen in people with pre-existing conditions, such as diabetes, high blood pressure, and obesity. These conditions are often closely linked to a poor diet, which lacks adequate intake of nutrients that are crucial for proper immune system function. By improving dietary intake of these important nutrients, the immune system can be strengthened with overall health improved to minimize risk of contracting Covid-19. The following are evidence based nutrients that boost the immune system:

Protein and Fats
High Quality Protein
Protein is vital for antibody production and helps to make immune cells, which reduces infection risk. Eating complete proteins, which contain all 9 essential amino acids, will help optimize protein’s role in the body. Some high quality sources of protein include poultry, bone broth, fish, eggs, hemp seeds and quinoa.

Omega 3’s & 6’s
Omega 3 fatty acids are healthy fats that work against pro-inflammatory Omega 6 fatty acids, which are found in certain nuts, vegetable oils, and tofu. Eating a ratio that is higher in Omega 3’s to Omega 6’s is important to reduce the harmful effects of Omega 6’s. Omega 3’s are naturally found in fish, seafood, eggs, and soybeans.

Vitamins
Vitamin A
Vitamin A forms a layer of mucus that lines respiratory and digestive tracts which enhances the function of the immune system. Having low vitamin A status increases your risk of respiratory disease and lung dysfunction, which makes this an essential nutrient for prevention and treatment of Covid-19. Vitamin A is found in animal sources, such as beef liver and eggs. Beta-carotene, which your body converts into Vitamin A, is found in plant sources such as yellow/orange colored fruits and vegetables, and in fortified grains and milk.

Vitamin C
Vitamin C is an antioxidant nutrient that is effective at combating free radical damage in the body, and calming inflammation. Vitamin C may also be useful for reducing susceptibility to viral respiratory infections. You can find natural food rich in Vitamin C, such as citrus fruits, kiwi, broccoli, and peppers.

Vitamin E
Vitamin E is an antioxidant that protects cells against damage from oxidative stress, a natural but harmful process that damages your cells and DNA. Getting adequate amounts of this vitamin boosts immunity and reduces inflammation. The best sources of Vitamin E are found in various nuts, seeds, vegetable oils, and avocados.

Vitamin D
Another antioxidant is Vitamin D, which keeps the immune system balanced. It can also help to keep bones strong during the pandemic, when physical activity may be limited. Good sources of vitamin D are salmon, eggs, chicken, mushrooms, and daily sun exposure.

Minerals
Selenium works by increasing the amount of immune cells and increasing antioxidant activity, which reduces harmful inflammation in the body. Likewise, Zinc helps to make an enzyme that reduces oxidative stress. Zinc also has an antiviral role, which improves immune function and reduces risk of viral infection. Good food sources of both selenium and zinc include fish, poultry, beef, dairy products, nuts, grains and beans.

While there are no specific foods or supplements to reduce the risk of getting Covid-19, being mindful of your nutrition during this time can improve your immune function and overall health. Incorporating these foods into well-rounded meals throughout the day while reducing intake of processed foods, saturated fats, added sugars, and refined grains/oils is recommended by nutrition experts to maintain good health and fight against potential infections.

Sources:

Christianne de Faria Coelho-Ravagnani, Flavia Campos Corgosinho, Fabiane La Flor Ziegler Sanches, Carla Marques Maia Prado, Alessandro Laviano, João Felipe Mota, Dietary recommendations during the COVID-19 pandemic, Nutrition Reviews, , nuaa067, https://doi.org/10.1093/nutrit/nuaa067

Stefan, Norbert et al. “Obesity and impaired metabolic health in patients with COVID-19.” Nature reviews. Endocrinology vol. 16,7 (2020): 341-342. doi:10.1038/s41574-020-0364-6

Barazzoni, R., Bischoff, S. C., Breda, J., Wickramasinghe, K., Krznaric, Z., Nitzan, D., . . . Singer, P. (2020). ESPEN expert statements and practical guidance for nutritional management of individuals with SARS-CoV-2 infection. Clinical Nutrition, 39(6), 1631-1638. doi:10.1016/j.clnu.2020.03.022

Wintergerst ES, Maggini S, Hornig DH. Contribution of selected vitamins and trace elements to immune function. Ann Nutr Metab. 2007;51(4):301-23. http://libproxy.txstate.edu/login?url=https://search-proquest-com.libproxy.txstate.edu/docview/232073457?accountid=5683.

Li P, Yin Y, Li D, Woo Kim S, Wu G. Amino acids and immune function. Br J Nutr. 2007;98(2):237-52. http://libproxy.txstate.edu/login?url=https://search-proquest-com.libproxy.txstate.edu/docview/213829638?accountid=5683. doi: http://dx.doi.org.libproxy.txstate.edu/10.1017/S000711450769936X.