11 Immunity-Boosting Foods You Need to Fight Off the Flu

If food is thy medicine, as Hippocrates prescribed, these are the superfoods to eat to stay sniffle-free this cold and flu season.

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Citrus fruit


You probably know that vitamin C is a go-to nutrient to get during colds—and a recent review of the scientific literature does suggest that taking vitamin C regularly can help us bounce back from a cold faster. But if you're reaching for orange juice, step away from the fridge. Go straight to the whole citrus fruit instead since it might actually be more of a boost to your health overall. Orange juice can be filled with extra sugar, and it doesn't include the helpful fiber that a whole fruit provides. If you're suffering from a cold, it might be better to reach for an orange instead of a glass of OJ. If you're craving juice, squeeze your own to ensure extra sugar isn't added. Here are more foods that are chock-full of vitamin C.

Bell pepper


Bell peppers contain more vitamin C than citrus fruits (almost twice your daily recommended amount), but are rarely thought of as a food that can help with immunity. 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. Bell peppers can be baked, roasted, or eaten raw, and they're also a great snack alone or when paired with dip or cheese. 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. Filled with vitamins A and C and the chemical compound sulforaphane, broccoli can help ward off the illnesses that are sure to come your way during flu season. A UCLA study in the Journal of Allergy and Clinical Immunology showed that sulforaphane switches on a set of antioxidant genes and enzymes in immune cells, protecting them from the kind of damage that can lead to disease. The health benefits of broccoli are most powerful when it's eaten raw, though steaming and light roasting are the next best prep methods. Also, a light steam—for three to four minutes, until crisp-tender—will free up more of the veggie's cancer-fighting sulforaphane. Adding broccoli to salads and dipping it in homemade yogurt-based dips are great ways to eat it raw. If you're going to cook it, consider buying frozen, as it's one of those vegetables that may actually be more nutritious when bought frozen.



Get the breath mints ready because garlic is really good for your immune health. Studies have shown that the antioxidant properties of garlic help to prevent colds and also shorten their duration. 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. You can eat garlic fresh from the supermarket (or better yet, your garden) or in supplement form. If you decide on the supplement, discuss with your physician first.



Spinach is packed with vitamins, including vitamin C and antioxidants, which make it a powerhouse of immune-boosting goodness. It's nutritionally best when eaten raw in salads, sandwiches, or in smoothies. Susan B. Dopart, MS, RD, CDE, author of A Recipe for Life by the Doctor's Dietitian, told Reader's Digest, "Green leafy vegetables are full of phytonutrients, which are non-vitamin minerals. These are extremely helpful not just for assisting the immune system with viruses, but with fighting things like cancer as well." Check out this list of other cancer-fighting foods to add to your diet.



Almonds are one of the original superfoods. They're packed with vitamins and minerals, including vitamin E, which is vital to the immune system. One half-cup of almonds has almost your entire daily recommended amount of vitamin E. Almonds are also a great source of protein and fiber. It's worth noting that the antioxidants in almonds are mainly found in their skin, so peeled or blanched almonds do not have the same impact on health as the raw nut. Almonds are great in salads or by themselves, and they also make a great on-the-go snack.



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 long list of health benefits. Tea is high in antioxidants that help the body fight illness, including cancer and heart disease. Scientists at Tufts University compared the "ORAC" (Oxygen Radical Absorbance Capacity, a measurement of the total antioxidant power of foods and other chemical substances) of black and green tea and 22 fruits and vegetables, and found green tea brewed for five minutes outranked even so-called superfoods on the produce list. Katherine Tallmadge, MA, RD, LD, spokeswoman for the American Dietetic Association, told webmd.com, "There doesn't seem to be a downside to tea. I think it's a great alternative to coffee drinking. Tea has less caffeine. It's pretty well established that the compounds in tea—their flavonoids—are good for the heart and may reduce cancer."

Chicken soup


It isn't a myth—chicken soup really does rev the immune system. Stephen Rennard, MD, of the University of Nebraska Medical Center, led a laboratory analysis of chicken soup and found that it has anti-inflammatory benefits that can help prevent cold symptoms. Dr. Rennard told abcnews.com, "My wife's grandmother says that chicken soup is good for colds. Just because your grandma said something doesn't mean that it's not true." The study was published in Chest, the journal of the American College of Chest Physicians.



If you're suffering from a cold or the flu, or simply hoping to prevent illness, reach for elderberry extract. Elderberry is one of the most effective immunity-boosting foods. Elderberry has been proven to reduce swelling of the mucous membranes and shorten the duration of the flu by up to three days. Packed with antioxidants and antiviral properties, it can also reduce flu symptoms if it's taken in the first 24 hours of onset. Elderberry can be taken as a syrup, tincture, or lozenge, and it 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. Research has shown that for elderly people in particular, probiotics can shorten the length of illnesses. Additionally, a 2011 analysis of ten studies found that taking probiotic supplements cut the number of upper respiratory tract infections by 12 percent and reduced the number of people who had at least one bad cold. "Gut health is the key to a healthy immune system," Dopart explains. "It's important that we step back and take a look at the whole picture of health. If someone isn't eating a healthy diet made up of whole, real food, and if their vitamin D levels are low, eating a lot of broccoli isn't going to do much for their immune system. 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. Here are more foods naturally rich in probiotics.

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