Using Nutrition to Improve Immunity During Covid-19
Lilly Roberts, Jie Zhu
Nutrition and Foods Program, School of Family and Consumer Sciences, Texas State University.

Unfortunately most critical cases of Covid-19 are seen in people with pre-existing conditions, such as obesity and diabetes. These conditions are often closely linked to a poor diet, which lacks adequate intake of essential nutrients for maintaining proper immune function. Research in nutrition science has found that 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.

Protein and Fats
Protein is vital for producing immune cells and antibody, which can reduce infection risk. Eating complete proteins, which contain all essential amino acids, will help optimize their role in the body. Some high quality sources of protein include eggs, poultry, fish, nuts and quinoa.

Omega 3 fatty acids are healthy fats that work against pro-inflammatory Omega 6 fatty acids which are found in certain nuts and vegetable oils.. 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 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 dysfunction, which makes this an essential nutrient for prevention and treatment of Covid-19. Vitamin A is found in animal sources, such as animal 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 is an antioxidant nutrient that is effective at combating free radical damage in the body, thus reducing inflammation. Vitamin C may also be useful for decreasing susceptibility to viral respiratory infections. You can find natural food rich in Vitamin C, such as citrus fruits, kiwi, broccoli, and peppers.

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.

Another antioxidant is Vitamin D, which keeps the immune system balanced. Vitamin D deficiency risk may increase during the pandemic when out-door 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 enhancing 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, whole 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.