A collection of immune system booters such as acai berries, fish, and bell peppers.

3 Foods to Boost Immunity

It's the start of summer, and the family may be basking in the sun while poolside when all of a sudden – achoo! A case of the summer sniffles strikes again. Headaches. Runny nose. Fever. The whole nine yards. But, if you'd rather reach for the sunblock instead of the tissues, pump up your meals with these immune-boosting ingredients.

The best foods for an immune system boost

To keep your immune system working its best, it’s more than just a healthy diet. Getting adequate sleep, exercise, and de-stressing is also important. There’s no single solution, but certain foods can help. Here are 3 foods to help boost your immunity.


Enjoy a classic summer barbeque with vitamin D-rich options such as trout and salmon. After being cooped up throughout the winter months, it's now more important than ever to get an extra boost of vitamin D. With the combination of sunshine and vitamin D rich foods, an immune regulating nutrient, your body will remain both happy and healthy. On the other hand, low levels of vitamin D can lead to increased susceptibility to infections and autoimmune diseases. Research has also shown that a therapeutic dose (1200IU/day) of vitamin D3 may decrease the likelihood of developing the common cold.1,2 Help reach your immune fighting needs with these other vitamin-D rich foods:3,4

  • Cod liver oil, 1tsp: 450 IU
  • Rainbow trout, 3 oz cooked: 645 IU
  • Sockeye salmon, 3oz cooked: 570 IU
  • White mushrooms (labeled with vitamin D), ½ cup raw: 366 IU
  • 2% fortified milk, 1 cup: 120 IU
  • Atlantic sardines, 2 (canned in oil): 46 IU
  • Fortified plant-based milk, 1 cup: 100-144 IU
  • Fortified ready-to-eat cereal, one serving: 80 IU

Bell peppers

Step aside oranges, this vitamin C powerhouse is coming through. One medium red bell pepper has 152mg of vitamin C. That's more than double the vitamin C content in a medium-sized orange!4 Red bell peppers are loaded with healthful antioxidants and are considered immune-boosting vegetables. Its vitamin C content can help prevent and treat both systemic and respiratory infections.5 It also has antimicrobial properties, which help to combat pathogens and protect the body.5 But, if you are looking to reap the benefits of disease prevention, research suggests a daily intake of 100-200mg of vitamin C through food. And, if you already have the summer sniffles, a larger dose may be needed.2 Remember to always choose whole foods over supplements and work with a dietitian to find safe, effective brands.

Luckily, there are countless ways you can make this delicious vegetable. Here are some tasty ways to enjoy bell peppers:

  • Fajitas. Enjoy them with whole wheat tortillas, lean chicken, and onions.
  • Stir-fry with broccoli, mushrooms, and tofu.
  • Stuffed peppers with tuna, quinoa, and herbs or ground turkey.
  • In skewers with chicken and tomato.
  • Tapenades with whole-wheat pita bread.
  • Grilled on the barbecue and served with your favorite protein.
  • Cooking eggs over easy inside a bell pepper ring.

Prevent food-boredom by incorporating other vitamin C-rich foods such as kiwi, broccoli, strawberries, brussels sprouts, grapefruit juice, and more.6 Perhaps try a vitamin C smoothie to enjoy on a warm summer day. Get your body immune-ready with this powerful nutrient!


This berry is more than just another health trend and insta-worthy photo opportunity. The polysaccharide component of the acai helps the body produce molecules responsible for recruiting white blood cells.7 In other words, this berry can help call on your immune system to assemble a small troop of infection-fighting cells.7 Research also shows that acai may also help alleviate symptoms associated with asthma, which will help you keep up with all the summer fun activities.7 It may also boost immunity to make you less susceptible to infections. So, brighten up your breakfast with an immune-fighting acai bowl. Not to mention, they are extremely refreshing on a hot day! Grocery stores even sell ready-to-go frozen packs of acai to make this gorgeous breakfast even more convenient and long-lasting. Also, acai smoothie packets, make the perfect popsicle!

Let's face it - there is never a great time to get sick. Keep your immune system soaring and let food be thy medicine! You may even discover a new favorite food or recipe. Be sure to stay tuned for the second part of our foods to boost immunity series.

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