11 Foods that Boost Your Immune System
From yogurt to spinach, tea to chicken soup, these superfoods will help you stay sniffle-free all year long.
Every product is independently selected by our editors. If you buy something through our links, we may earn an affiliate commission.
Gearing up to fight
Your immune system is your body’s first defense against virus and illnesses, so it’s important to make sure that it’s strong and in fighting condition. One of the best ways to do this is to eat plenty of essential nutrients and protein. A diet rich in colors from varied sources of fruits and vegetables is a great way to start, according to Roger E. Adams, PhD, a nutritionist and dietitian from Katy, Texas. “Fruits and veggies provide plenty of antioxidants, water, fiber, and other nutrients to help you get off to a promising start,” he says. “It’s important to have balance, however, since no single food, nutrient, substance, or activity will boost this system alone.” Here are some of the best foods to pile on your plate to keep your immune system in tip-top shape.
Get the breath mints ready because garlic is really good for your immune health. Garlic has been used for centuries to support the immune system and provide protection against myriad health conditions, including heart disease and Alzheimer’s disease. “The sulfuric compounds that garlic contains are most potent when raw since heat inactivates sulfur enzymes,” says Frances Largeman-Roth, RDN, dietitian and author of Eating in Color. “To enjoy raw garlic, use it in pesto and also in chimichurri, which also contains shallots, chilies, vinegar, cilantro, parsley, oregano, and olive oil.”
You’ve probably heard that vitamin C is a go-to nutrient to take during colds—research doesn’t really support this, though a review of scientific literature suggests that some people bounce back from a cold quicker—and have milder symptoms—if they take vitamin C. “Citrus fruits, like oranges, lemons, grapefruit, and limes are all rich sources of vitamin C, which may help shorten the length of your cold or flu by about a day,” says Largeman-Roth. “Oranges and grapefruit can be eaten as snacks of course, added to smoothies and salad dressings, squeezed into regular or sparkling water, and also used to make homemade ice pops.” (Check out these other foods that are chock-full of vitamin C.)
Bell peppers contain more vitamin C than citrus fruits (almost twice your daily recommended amount). Red bell peppers pack more of a nutritional punch than green, yellow, and orange bell peppers, though they are all considered to be good choices for a healthy diet. “Crunchy bell pepper slices make a great addition to a crudité platter and are also delicious sliced thinly in sandwiches, salads, and wraps,” suggests Largeman-Roth. “You can also add them to pasta dishes and stir-fries.” The next time you’re fighting a cold, consider adding a bell pepper or two to your meal to give your body an extra boost. (It still counts if it’s on pizza!)
Whether you love it or hate it, broccoli is quite the superhero when it comes to boosting your immune system. “We often think of broccoli for its cancer-fighting properties, but it’s also an immune-booster thanks to its high content of sulfuric compounds called glucosinolates,” says Largeman-Roth. “One cup of cooked broccoli has 74 milligrams of vitamin C, which is nearly as much as an orange.” She recommends eating it steamed or roasted, adding it to salads, or dipping it in homemade yogurt-based dips. If you’re going to cook it, consider looking in the freezer aisle, as it’s one of those vegetables that may be more nutritious when you buy it frozen.
Spinach is packed with vitamins, including vitamin C and antioxidants, which make it a powerhouse of immune-boosting goodness. It’s also rich in iron, with 6 milligrams in just one cup. “Iron is necessary for the immune system to function properly,” says Largeman-Roth. She recommends adding baby spinach to your salads and sauteing regular spinach leaves with garlic and pine nuts. “Just be sure to enjoy spinach with a food high in vitamin C to absorb all of the iron,” she adds. (Check out this list of other cancer-fighting foods to add to your diet.)
Almonds are one of the healthiest nuts you can eat: They’re packed with vitamins and minerals, including vitamin E, which is vital to the immune system. Another key nutrient found in almonds is zinc, which has immune system-boosting benefits. “Zinc is involved with all cells, including inflammatory cells and skin cells, and protein and collagen synthesis,” says Largeman-Roth. “Without enough zinc in the body, wounds may take longer to heal.” She recommends enjoying almonds as a snack or chopping them up and using them to top your yogurt, oatmeal, cereal, and muffins.
Sipping brewed tea is one of the oldest ways to give your body the tools it needs to build a strong immune system. Each type of tea—green, black, white, or oolong—comes with its own list of health benefits. “Darker teas like black and green teas are rich in antioxidants that can help scavenge free radicals in our body,” says Adams. “Free radicals can cause early cell death and also alter cellular functioning, so keeping a good supply of antioxidants are always a good idea.” He recommends incorporating some freshly brewed black or green tea throughout the day into your normal beverage rotation.
It isn’t a myth—chicken soup really does rev the immune system, especially if it’s hearty with plenty of chicken. “The protein boost will ensure you have the building blocks necessary to keep your immune system in shape and the broth adds a boost of hydration,” says Adams. “Chicken soup, and other vegetable-based broth soups, are high in vitamins A and C, magnesium, phosphorus, and antioxidants.” He recommends incorporating a cup of broth-based soup with protein and veggies as a meal several days per week as an easy way to boost your body’s defenses against illness.
If you’re suffering from a cold or the flu, or simply hoping to prevent illness, reach for elderberry extract. Research published in the Journal of Function Foods found that elderberry may minimize flu symptoms. Packed with antioxidants and antiviral properties, it can impact flu signs if it’s taken in the first 24 hours of onset. Elderberry can be taken as a syrup, tincture, or lozenge, and has been used for centuries to treat ailments and wounds.
Consider yogurt a friend to the immune system. Its benefits come mainly from probiotics (friendly bacteria that have been found to improve gut health) which may improve immune health, according to research published in the journal Annals of Nutrition and Metabolism. “Gut health is the key to a healthy immune system,” explains Susan B. Dopart, registered dietitian and author of A Recipe for Life by the Doctor’s Dietitian. “Gut health plays a huge role in keeping an immune system strong, and probiotics are extremely important.” When choosing a yogurt, make sure that the label includes the phrase “contains live and active cultures” and a minimum amount of sugar to score maximum benefits.
Their sweet flavor might convince you that they’re not all that healthy, but sweet potatoes offer quite a lot of immune system benefits. “Due to their rich colors, sweet potatoes are rich in vitamin A and beta carotene, both powerful antioxidants,” says Adams. Sweet potatoes can be baked or roasted, and they go great in salads. Need ideas? (Try these healthy alternatives to your favorite potato dishes.)
- Roger E. Adams, PhD, nutritionist and dietitian in Katy, Texas
- The Cochrane Database of Systematic Reviews: "Vitamin C for Preventing and Treating the Common Cold"
- Frances Largeman-Roth, RDN, dietitian and author of Eating in Color
- USDA FoodData Central: "Peppers"
- InformedHealth: "How Can I Get Enough Iron?"
- Journal of Functional Foods: "Anti-influenza activity of elderberry (Sambucus nigra)"
- Annals of Nutrition and Metabolism: "Beneficial Effects of Probiotic Consumption on the Immune System"
- Susan B. Dopart, MS, RD, CDE, author of A Recipe for Life by the Doctor's Dietitian