Foods that boost the immune system

When your nose is stuffy, and you can’t stop coughing, the best Rx may be . . . in your kitchen. “Certain foods are high in nutrients that boost your health,” explains Kathy McManus, RD, director of the department of nutrition at Brigham and Women’s Hospital in Boston.

Here are ten foods that are scientifically proven to help kick those cold and flu bugs.

Whole Grains

They’re loaded with zinc, which is vital for maintaining a healthy immune system. Try whole-grain spaghetti with tomato sauce or brown rice with veggies.

They contain vitamin B6, which helps your body fight infection. Eat your bananas sliced over whole-grain cereal and double your germ-busting power.

Cayenne Pepper

Capsaicin, the active ingredient in the spice, beats congestion by thinning the mucus in your nasal passages so you can breathe freely again. Sprinkle some in soup or on a bean burrito.

Sweet Potatoes

They’re one of the best sources of beta-carotene (a form of vitamin A), which your body needs to make enough white blood cells to fight off infection. Eat them mashed or baked.


Allicin, one of the active components in freshly crushed garlic, can zap viruses by blocking the enzymes that lead to infection. Use it in a Caesar salad, pesto sauce, or guacamole.

Quercetin Powerhouse Products: Apples, Onions, Broccoli, and Tomatoes

Quercetin is one of many thousands of flavonoids—substances that are responsible for plants’ colors, as well as many of their health benefits. La Puma says that in research performed on mice, stressful exercise increased flu susceptibility but quercetin canceled out the negative effects. Tip: When buying tomatoes, consider choosing organic, which La Puma says have higher levels of quercetin than conventionally grown ones (the same is true for lycopene in tomatoes).

Chicken Soup

It’s not a suburban legend: Chicken soup really does have healing properties, according to La Puma. A steaming bowl of soup (unappetizing language alert) “reduces mucus and facilitates coughing it up.” And it seems that chicken soup is more effective at the job than hot water, according to research cited by La Puma. To get the anti-inflammatory and other health benefits of produce too, the doctor suggests making chicken soup with vegetables rather than using store-bought condensed soup or cooking with chicken alone.

Green Tea

Add fighting the flu to the long list of green tea’s health benefits, which also include fighting cancer and heart disease and possible links to “lowering cholesterol, burning fat, preventing diabetes and stroke, and staving off dementia,” according to WebMD. Green tea is high in “anti-viral activity against influenza,” says La Puma, citing studies involving green tea from the Dr. Rath Research Institute in Santa Clara, Calif., and the Department of Biotechnology, College of Engineering, Yonsei University in Seoul, South Korea. While all kinds of tea are made from the same leaves, white and green teas contain higher levels of catechins—the flavonoids thought to be responsible for tea’s antiviral properties—than oolong and black teas.

Vitamin D–Rich Foods: Salmon, Light Tuna, Sardines, Milk, and Cereal

Vitamin D has been a hot topic in the news recently, with stories about the sunshine vitamin’s many health benefits dovetailing with reports that suggest that many of us don’t get enough of it. La Puma says experiments in the 1940s showed that mice that received diets low in vitamin D were more susceptible to experimental swine flu infection than those that received adequate vitamin D. While the same has not yet been proven in humans, La Puma and many other experts believe that getting sufficient vitamin D can offer protection against swine flu—the vitamin is believed to cause the production of antimicrobial substances in the body. “In winter, too little vitamin D is made in your skin, because the angle of the sun is too low,” says La Puma. “And winter is when you get flu.

Chiles Such as Serranos, Jalapeños, and Poblanos

Spicy peppers don’t just help clear your sinuses, they’re also a great source of vitamin C, which “has been tested in influenza A and been shown to reduce the incidence of pneumonia that comes with flu,” says La Puma. The vitamin has antiviral properties and stimulates antibody production, explains La Puma. Not a chili-head? Sweet red bell peppers are also packed with vitamin C, as are guava, kiwi, oranges, green bell peppers, strawberries, Brussels sprouts, cantaloupe, and papaya, according to the USD.
Back to Newsletter