By: CR Bourgeois, MS, RDN, LD
As cold and flu season approaches, many people are roaming the grocery store aisles in search of immune boosting remedies that promise to keep illness away. But can food really support your immune system? The short answer – yes, but maybe not in the way you’d think.
Despite what some product advertising may lead you to believe, no single food can prevent colds or the flu. However, a balanced eating pattern provides the nutrients your immune system needs to work at its best.1
How Nutrition Affects Immunity
Your immune system is a complex network of cells, tissues, and organs that all work together to protect your body against viruses, bacteria, and other germs. But your immune system doesn’t just turn on with the flip of a switch. It requires energy and nutrients to perform its necessary tasks.
Several nutrients play important roles in immune function, such as:
- Vitamin C supports immune cell activity and acts as an antioxidant.
- Vitamin D helps regulate immune responses.
- Protein is required to produce antibodies and immune cells.
- Vitamin A supports healthy skin and mucosal barriers.
- Zinc helps immune cells grow and fight infections.
Rather than focusing on one single nutrient, prioritize eating a well-balanced diet rich in fruits, vegetables, lean proteins, and healthy fats. A nutrient dense diet makes it easier for you to eat enough of these immune boosting nutrients.
What Foods Support Immune Function?
Some foods provide nutrients that are linked to healthy immune function, but no food can magically keep you healthy on its own. It’s more of a team effort that comes in the form of a well-balanced diet. So, what are some key players you can add to your grocery list this season? I’m so glad you asked!
Colorful Fruits and Vegetables
The produce section can be a great place to find good sources of vitamin C, vitamin A, and many other immune-boosting nutrients. Citrus fruits, berries, leafy greens, sweet potatoes, and bell peppers are just a few examples of fruits and veggies that contain vitamins, minerals, and antioxidants that support overall health.
Foods Rich in Zinc
Zinc is important to your immune system, but its main claim to fame is its role in supporting white blood cells.4 White blood cells act as your body’s first line of defense, destroying harmful bacteria and viruses. Sources of zinc include seafood, red meat, beans, and nuts.
Lean Protein Sources
Protein contains amino acids that the body uses in several different ways. These amino acids are essential to building antibodies, repairing tissue, and creating chemical messengers that communicate where your immune system is needed most. Excellent sources of lean protein include chicken, fish, eggs, tofu, Greek yogurt, and beans.
Fermented Foods
When talking about the immune system, we of course must highlight the importance of gut health. A large portion of the immune system has been linked to the gastrointestinal tract. Eating fermented foods with beneficial bacteria, such as yogurt, Kiefer, and sauerkraut can support overall wellness.3
Hydrating Foods and Fluids
We also can’t forget the importance of staying hydrated. Hydration is essential to a healthy immune system. Water, soups, fruits, veggies, and other water-rich foods can help support your daily hydration needs.
Lifestyle Habits Matter Too
Nutrition is only one piece of the puzzle. Other lifestyle factors play a role in immune health.
These include:
- Getting adequate sleep2
- Regular physical activity
- Managing stress
- Practicing good hand hygiene
These habits, along with a well-balanced diet, can help your body stay ready to fight infections and stay healthy during cold and flu season.
References:
- Munteanu C, Schwartz B. The relationship between nutrition and the immune system. Front Nutr. 2022;9:1082500. Published 2022 Dec 8. doi:10.3389/fnut.2022.1082500
- Guo L, Huang Y, He J, et al. Associations of lifestyle characteristics with circulating immune markers in the general population based on NHANES 1999 to 2014. Sci Rep. 2024;14(1):13444. doi:10.1038/s41598-024-63875-2
- Leeuwendaal NK, Stanton C, O’Toole PW, Beresford TP. Fermented Foods, Health and the Gut Microbiome. Nutrients. 2022;14(7):1527. Published 2022 Apr 6. doi:10.3390/nu14071527
- Stiles, L.I., Ferrao, K. & Mehta, K.J. Role of zinc in health and disease. Clin Exp Med 24, 38 (2024). https://doi.org/10.1007/s10238-024-01302-6
