Immune-Boosting Foods and Tips to Fight the Flu

Immune-Boosting Foods and Tips to Fight the Flu

To make sure that this flu season doesn’t get you down, be sure to follow these tips and try these immune-boosting foods.

Immune-Boosting Foods and Tips

Your gut is the largest part of your immune system, so it is important to keep it healthy and working properly. The best way to achieve this is with a daily dose of probiotics to boost good gut bacteria. Studies show that sugar and refined carbs can cause damage to our gut, while fermented foods can heal because they are highest in bacteria-boosting probiotics. Examples of fermented foods include:

  • Kombucha
  • Pickles
  • Kimchi
  • Yogurt
  • Cabbage

We all know that consuming a wide variety of foods is good for us. It is the easiest way to build up a strong immune system because the variety of nutrients our bodies receive help fight inflammation and fortify cells. Bonus points for eating this way year-round so that our bodies have enough time to regulate infection-fighting antibodies and anti-inflammatory compounds.

Fortify Your Body With Vitamins

Certain vitamins and minerals are better at providing immune-boosting benefits than others. While it is important to know what to eat, it may also be helpful to know the science behind why we should choose these immune-boosting foods. Below is a list of the most important vitamins and minerals to consume, foods that contain each vitamin or mineral, and a brief explanation of why these nutrients are so essential, especially during cold and flu season.

Vitamin A:

Commonly Found In: Animal foods like eggs, fish oil, butter, and liver

Why It’s Important: We can become vulnerable to infectious organisms when our internal membranes are weakened. Affected membranes include tissue membranes, mucous membranes (in our mouth and nose), and cell membranes. Vitamin A helps strengthen and support healthy membranes through its antioxidant and anti-inflammatory properties.


Commonly Found In: Brightly colored fruits and veggies such as papaya, carrots, and kale

Why It’s Important: Beta-Carotene is in the same family as Vitamin A. Because of this, it helps to promote immunity with its antioxidant and anti-inflammatory properties.

Vitamin C:

Commonly Found In: Kiwi, citrus fruit, berries, and red peppers

Why It’s Important: Most people inherently group Vitamin C in the cold-prevention category and for good reason. Vitamin C supports infection-fighting antibodies called T-cells, B-cells, and phagocytes. Phagocytes are cells that protect the body by ingesting and eliminating harmful bacteria. As a bonus, Vitamin C also promotes healthy skin and wound healing.

Vitamin E:

Commonly Found In: Spinach, sunflower oils and seeds, peanut butter, avocado, almonds, and wheat germ

Why It’s Important: Similar to Vitamin C, Vitamin E helps to support T- and B-cell function. It also has antioxidant and anti-inflammatory properties. Interestingly, certain studies have shown that Vitamin E can boost vaccine responses in the elderly population, making the vaccinations more effective against illness.

Vitamin D:

Commonly Found In: Mushrooms, oily fish, egg yolks, and fortified milk

Why It’s Important: Vitamin D plays many important roles in the body. It has both anti-inflammatory properties and the ability to fight infection through the activation of T-cells and cytokines. Cytokines are proteins that control cell behavior during times of cell injury, infection, and inflammation. Studies have shown that Vitamin D may help protect against cancer, cardiovascular disease, dementia, and even the common cold. Not only can we get Vitamin D from the foods we eat, we can also get Vitamin D from exposure to sunlight. As little as 15 minutes of sunlight per day will increase these healthy benefits!

Vitamins B5, B6, and B12:

Commonly Found In: Vitamins B5 and B6 are found in whole grains, nuts, and seeds while Vitamin B12 is found in animal foods like yogurt, liver, and beef. If you’re a vegetarian, fermented foods like sauerkraut and tempeh contain small amounts of Vitamin B12. A supplement may be recommended to meet your daily needs in this case.

Why It’s Important: Vitamins B5 and B6 work to kickstart your antibodies to fight infections, while Vitamin B12 helps to produce more B-cells (responsible for fighting infections) and healthy red blood cells (responsible for the transport of oxygen and the removal of carbon dioxide throughout the body).


Commonly Found In: Root vegetables, oysters, shellfish, seafood, and almonds

Why It’s Important: Zinc is essential for maintaining a healthy, functioning immune system. If you have a zinc deficiency, you are at an increased risk for infections. Zinc works as an antioxidant in conjunction with Vitamin E and selenium and therefore enhances cellular function and increases the production of infection-fighting antibodies. Many over-the-counter cold medications contain zinc for this very reason. Be careful with supplementation, as an excess of zinc can work in the opposite sense and will decrease immune function.


Commonly Found In: Lentils, meats, molasses, raisins, and leafy greens such as spinach

Why It’s Important: Iron is extremely important for energy production because of its role in the transportation of oxygen throughout the body. Like zinc deficiency, a true iron deficiency will put you at a greater risk for frequent infections and a constant feeling of tiredness. Be aware with supplementation, though, as too much iron can speed up bacterial growth.


Commonly Found In: Brazil nuts, nutritional yeast, brown rice, wheat germ, and salmon

Why It’s Important: Selenium is an important antioxidant that works in conjunction with Vitamin E to produce glutathione. Glutathione is a key antioxidant that protects the body’s cells from free radicals and enhances detoxification of cells. Incorporating selenium-rich foods is recommended over supplementation due to the negative effects of selenium overdose.


Commonly Found In: Avocado, leafy greens, almonds, brown rice, and soy/tofu

Why It’s Important: Magnesium aids in several various functions within the body from cardiac and brain function to enzyme activity. It is well-known for its anti-inflammatory and immune-boosting properties, while helping to strengthen our bones and muscles. Magnesium is key for regulating women’s hormones. Low magnesium levels in women can contribute to more intense PMS and menopause symptoms.

Recipes for Immune-Boosting Foods

Looking for creative, new ways to incorporate some of these vitamin- and mineral-rich foods? Here are the links to 3 great recipes to get you started!

Salmon and Brown Rice Salad

salmon and brown rice

Grilled Peach and Apricot Salad

grilled peach and apricot salad

Food52 / via

Charred Corn and Avocado Salad

Charred Corn and Avocado Salad

Food52 / via

Please contact me if you have any questions about these immune-boosting foods or want a free nutrition consultation!

Schedule a Nutrition Consultation

Sarah Brunner Registered Dietician at Elite Sports Clubs

Written by Sarah Brunner, RDN, CD; Elite Sports Clubs Registered Dietitian

Sarah is certified in food allergies/intolerances and nutritional counseling, Academy of Nutrition and Dietetics; has a certificate in Dietetics from Mount Mary University; and a BA in Education and Mathematics from the University of Wisconsin – La Crosse.