Top 10 Foods to Build Immunity

By Ana Reisdorf, MS, RD

There are plenty of medications to help alleviate cold and flu symptoms, but what simple things can you do to preventillness in the first place? Lifestyle habits like exercise and eating well have been shown to boost immunity. Certain foods can help keep your immune system in tip-top shape. Learn about some of these immune-boosting foods below.

How Does Food Affect Your Immune System?

Much of the research around boosting immunity with diet has to do with how food changes the bacterial makeup of the digestive tract. What we put into our body directly impacts how well we can fight off illness. There’s a huge link between gut health and overall health, and certain foods can be especially beneficial for immunity. 

Foods that are popular in the standard American diet — often characterized by being high in sodium, sugar, saturated fat and cholesterol — promote inflammation and negatively impact gut health and the immune system. On the other hand, minimally processed, whole foods — especially fruits and vegetables — are high in antioxidants, fiber, vitamins and minerals that work against inflammation and help the body fight illness.  

Furthermore, deficiencies in micronutrients like zinc, selenium and vitamins A, C and E can reduce your immune defense, making it important to eat foods that offer these nutrients.

10 of the Best Foods to Boost Your Immunity 

1. Citrus Fruits like oranges, lemons, limes, and grapefruit are high in Vitamin C, which is thought to increase white blood cell production to help fight illness. You might drink orange juice when you're sick for this reason, but eating citrus in its whole form is even better.
2. Bell Peppers, especially red ones, contain about twice as much Vitamin C as citrus fruits. They’re also rich in beta carotene, an antioxidant that may improve immunity.
3. Broccoli is one of the healthiest vegetables around, full of vitamins A, C and E, fiber and antioxidants that help stave off illness. Cooking it can reduce its nutrient content, so eat it raw when possible.
4. Berries are rich in antioxidants and immune-boosting pigments called anthocyanins, which give them their red, blue and purple coloring.
5. Dark leafy greens like spinach, kale and collard greens are packed with antioxidants, Vitamin C and beta carotene, which can help fight off infections.
6. Garlic and ginger are great for flavoring many dishes, and are also full of immune-boosting compounds. Garlic is known for being rich in sulfur-containing compounds that improve immunity, such as allicin, while ginger can reduce inflammation and nausea as well as soothe a sore throat.
7. Nuts and seeds like almonds and sunflower seeds are rich in Vitamin E, an important fat-soluble vitamin and antioxidant for immunity. Pumpkin seeds, hemp seeds, cashews, peanuts and pine nuts are also good sources of zinc.
8. Turmeric is an Indian spice known for its characteristic yellow pigmentation. The active component of turmeric is curcumin, for which there is a lot of evidence of immune-boosting properties. It’s a known anti-inflammatory and can help repair cell damage in your body.
9. Yogurts that contain live and active cultures, or probiotics, are particularly good for your gut bacteria and immune defenses. Many are also fortified with Vitamin D, which supports immunity. Look for plain varieties without added sugar.
10. Green tea is particularly rich in epigallocatechin gallate, or EGCG, an antioxidant known to boost immune function. It’s also a good source of the amino acid L-theanine, which may help protect your body from illness by promoting the production of germ-fighting compounds.

You might already enjoy many of the above foods; if not, they can easily be added to your routine. Eating a wide variety of immune-boosting foods may have you enjoying a healthier year ahead, with fewer colds and illnesses.