12 Foods That Strengthen Your Immune System

It's that time of year again—and no, we're not talking about the season of pumpkin spice and peppermint flavorings. We're talking about flu season. Even if you’re armed with copious amounts of hand sanitizer and Emergen-C, there's still a chance you’ll fall victim to these nasty viruses. So we talked to Torey Jones Armul, MS, RDN, CSSD, and Vandana Sheth, RDN, CDE, both spokespeople for the Academy of Nutrition and Dietetics, to find out 12 immunity-boosting foods that can help cut down on the amount of time we're under the weather. (Because who wants to spend their sick days actually, you know, feeling sick?)

Chili Peppers

"Break out the chili recipe, because chili peppers are one of the most underrated sources of vitamin C," Jones Armul says. "By volume, chili peppers are the single highest food source of vitamin C, although it’s unlikely for someone to eat more than a bite or two." To reap the benefits, she recommends getting out your crockpot to make homemade soup, or adding some of the pepper to sauces.
Wondering why vitamin C seems to be one of those universally accepted flu remedies? "It helps protect us from infection and boosts our immunity by enhancing our body's antibodies," Sheth explains.


You may be familiar with the fact that carrots are one of the best sources of beta-carotene, but what does this antioxidant actually do? "Antioxidants help protect cells from damage, so they’re beneficial when fighting infection," Jones Armul says. Beta-carotene turns into vitamin A in the body, and just munching on 10 baby carrots is enough to get your entire day's worth of the vitamin.


Both Jones Armul and Sheth say that oysters are especially great when dealing with the flu, as they're a good source of zinc. "Zinc is critical to a well-functioning immune system," explains Jones Armul. Sheth adds that it can also help reduce how awful your flu is, along with how long it lasts. Just three oysters meet 100 percent of our daily zinc needs, Jones Armul says. But if you simply can't stomach the thought of oysters when you're sick, she notes that a more palatable option is a cup of fortified cereal, which meets the daily recommendation of zinc. Lean meat like chicken and fish, along with milk (all the better to splash on your cereal), are also good options according to Sheth.


There's a reason this leafy green has taken the produce world by storm in the last few years. Just one cup is packed with vitamins A and C (that's "350 percent of the daily recommended vitamin A and 90 percent of the vitamin C," Jones Armul says). "Cup for cup, cooked greens are more nutrient-dense than raw, although the best form is whichever you’re most likely to eat!"


Be sure to add mushrooms to your chicken noodle soup (more on that later). Sheth says they can help boost immunity by "enhancing our body's production of cytokines," which are proteins that help fight infections.

Orange Juice

Even though those store-bought labels of OJ boast high amounts of Vitamin C, Jones Armuls says that making your own juice gives you even more benefits (plus, it has less added sugar). Sheth also recommends other fruits, like grapefruit, tangerine, and strawberries for their high vitamin C content.

Chicken Noodle Soup

It's a classic for a reason. "Hot liquids such as herbal teas and soups can be comforting and soothing," says Sheth. She also notes that there are studies that show that soups with veggies (like the aforementioned carrots) can be anti-inflammatory and help with flu-like symptoms.


Another veggie high in vitamin C, broccoli is a solid immunity-boosting option for people who are trying to watch their sugar intake.

Sweet Potatoes

Sweet potatoes, like carrots, are chock-full of good-for-you vitamin A and they're also an excellent source of vitamin C. "While most research says vitamin C can’t actually prevent catching the flu," Jones Armul says, "it may help reduce the duration of it."


Sheth recommends ginger because it contains chemicals that have immunity-boosting powers. She says to simply add it to your meals as a flavor enhancer, or use shredded ginger in a hot beverage, like tea.


Though it may make your breath a little stinky, garlic is great for your immune system. "Garlic has the capacity to fight bacterial and viral infections," Sheth says.


These nuts are rich in vitamin E. When your body doesn't get enough vitamin E, it can impair your immune system, Jones Armul says. Almonds are one of the best foods you can eat to get this vitamin; one ounce meets 36 percent of the daily amount your body needs.

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