COVID-19 Nutrition

How Proper Nutrition Impacts Your Immune System

Many popular articles claim that individual nutrients or foods can fight disease, however, this is a common misconception. Eating one specific food or nutrient cannot increase or “boost” your immune system, however, regularly eating a balanced diet over the course of your lifespan can shorten the duration of infections and improve your immune response.


The human body is made up of proteins, including the immune systems. Eating enough calories over the course of the day in addition to eating enough protein is important for the body’s immune system and recovery response. Protein foods consist of seafood, lean meats, poultry, eggs, low-fat dairy products, beans, peas, nuts, seeds, and soy products.

Vitamin A

Vitamin A plays an important role in immune function by keeping the skin and tissues of the mouth, stomach, intestines, and respiratory system healthy and functional. Vitamin A is found in foods such as sweet potatoes, cantaloupe, carrots, broccoli, spinach, red bell peppers, salmon, mango, apricots, eggs, and some foods labeled as “vitamin A fortified,” such as milk or certain cereals.

Vitamin E

Vitamin E functions as an antioxidant and has been associated with immune function. Foods that add more vitamin E into your diet include nuts, seeds, vegetable oils, and fortified cereals.

Vitamin C

Vitamin C has been shown to support the immune system by stimulating the formation of antibodies and it may shorten the duration of illnesses. Foods rich in vitamin C include kiwi, 100 percent orange juice, cantaloupe, broccoli, leafy greens, strawberries, tomatoes, red peppers, sweet and white potatoes.


Zinc plays a large role in the integrity of the body’s tissues, helps wounds to heal, and functions as an antioxidant within the body. Zinc is found in lean meats, poultry, eggs, nuts and beans.

While we cannot fight or prevent disease with nutrition alone, it is important to keep in mind that eating a balanced and healthy diet at all times of the year plays an important role in optimizing health and immune function.

-Samantha Manero, MS, RD, LDN, is a registered dietitian with Steward Health Care

To find a doctor or schedule an appointment, visit Steward DoctorFinder™.


  • Li, P., Yin, Y.-L., Li, D., Woo Kim, S., & Wu, G. (2007). Amino acids and immune function. British Journal of Nutrition, 8(2). doi:
  • Huang, Z., Liu, Y., Qi, G., Brand, D., & Zheng, S. G. (2018). Role of Vitamin A in the Immune System. Journal of clinical medicine, 7(9), 258. doi:
  • Lee, G. Y., & Han, S. N. (2018). The Role of Vitamin E in Immunity. Nutrients, 10(11), 1614. doi:
  • Wintergerst, E. S., Maggini, S., & Hornig, D. H. (2006). Immune-Enhancing Role of Vitamin C and Zinc and Effect on Clinical Conditions. Annals of Nutrition and Metabolism. doi:
  • Shankar, A. H., & Prasad, A. S. (1998). Zinc and immune function: the biological basis of altered resistance to infection. The American Journal of Clinical Nutrition, 68(2), 447S–463S. doi:
  • Klemm, S. (2019, December). Support Your Health With Nutrition. Retrieved from