Immune System

We know the immune system is important for staying healthy, but what exactly is it and what can we do to support it?

The immune system is a complicated network of cells, tissues, and organs in your body and is the first line of defense against disease and infection. A healthy immune system is important at every age. A strong immune system helps protect against infections from bacteria and viruses as well as helps to heal wounds.

Focusing on eating a variety of nutrient-rich foods and adopting healthy lifestyle behaviors plays an important role in its function.

Your Immune System

There are micronutrients in the foods we eat that play a key role in supporting the immune system

An important step you can take for your immunity is to ensure you’re eating a balanced diet in order to fulfill the daily requirements of these micronutrients. Find out how each of them serves your body and which foods you can find them in.

Vitamin D

What it does: Works with calcium and phosphorus to make strong bones.

Where to find it: Mushrooms are the only source of vitamin D in the produce aisle and one of the few non-fortified food sources. It can also be found in salmon, fortified milk & eggs.

Vitamin C

What it does: Acts as an antioxidant to help protect cells from damage. Vitamin C also helps the body absorb iron and supports proper immune function.

Where to find it: Citrus fruits, berries, melons, tomatoes, kiwifruit, bell peppers and broccoli.


What it does: Helps the immune system fight off invading bacteria and viruses.

Where to find it: Mushrooms, lobster, beef, pork, Swiss cheese and nuts.

Vitamin E

What it does: Fights off invading bacteria and viruses while helping widen blood vessels to prevent blood clots.

Where to find it: Almonds, hazelnuts, sunflower seeds, peanut butter, pumpkin, and spinach.

Vitamin A

What it does: Vitamin A is important for normal vision, the immune system, and reproduction. It also helps the heart, lungs, kidneys and other organs function properly.

Where to find it: Spinach, carrots, dairy products, liver, and fish.

Vitamin B6

What it does: Plays an important role in immune function. It’s also needed for enzyme reactions and helps the body use and store energy from protein and carbohydrates.

Where to find it: Shiitakes, bananas, squash, chickpeas, wheatgerm, chicken and tuna.

Vitamin B12

What it does: Helps keep the body’s nerve and blood cells healthy and helps make DNA.

Where to find it: Found in salmon, tuna, beef, chicken, eggs, milk, and nutritional yeast.


What it does: Helps to keep tissues healthy by preventing cell damage.

Where to find it: Crimini and portabella mushrooms, grains, Brazil nuts, halibut, ham, beef and turkey.


What it does: Carries oxygen via blood cells throughout the entire body, and is essential in the production of red blood cells.

Where to find it*: Oysters, legumes, potatoes, red meat, seafood, tofu and spinach.


What it does: Needed by the body to make DNA and other genetic material.

Where to find it: Asparagus, broccoli, brussels sprouts, kidney beans, edamame and avocado.


What it does: Used by the body to make energy, connective tissues and blood vessels. Helps maintain the nervous and immune systems.

Where to find it: Shiitakes, potatoes, cashews, turkey, spirulina and shellfish.


What it does: Probiotics are “good” bacteria that promote health by working to balance good & bad bacteria within the colon.

Where to find it: Cultured dairy products such as yogurt and in fermented foods such as kimchi.

Immune Support

The immune system is the body’s first line of defense against disease and infection.

A healthy and strong immune system helps protect against infections from bacteria and viruses. There are many lifestyle habits you can adopt to support a healthy immune system.


+ Get enough sleep

+ Manage your stress

+ Consume less sodium, saturated fat and added sugars

+ Be physically active, aim to get 150 minutes of moderate to vigorous activity weekly

+ Include a variety of proteins in your weekly meals

+ Choose whole grains more often than refined grains

+ Eat a wide range of fruits and vegetables, including mushrooms!

Registered Dietitians

Tamara Saslove & Elis Halenko, Registered Dietitians


*Keep in mind that animal-based sources of iron are more easily absorbed, and eating animal-based sources along with plant-based sources can help the absorption of the plant-based iron. Further, adding a source of vitamin C, like lemon juice, can also make plant-based sources of iron easier to absorb.