A steaming bowl of chicken soup and a tall glass of orange juice may actually help ward off or fight cold and flu symptoms, according to Health Center registered dietitian Amy DiCioccio.

But what causes these foods to help and what is just myth? DiCioccio spoke with NBC Connecticut’s Yvonne Nava about which foods help those who are feeling a bit under the weather and why.

“The biggest chunk of research about preventative medicine in both common cold and flu is centered around vitamin C,” says DiCioccio. “You’re going to really want to aim for about 1,000 mg of vitamin C per day.”

A medium orange only provides about 70 mg of vitamin C, a large orange may be closer to 100 mg, so DiCioccio recommends vitamin C supplements, like Emergen-C, that can be mixed with water. She says this is also helpful, because it is a way to take in more fluids.

Broccoli is another source of vitamin C and DiCioccio says steaming it is the most beneficial way to prepare it. She also says red peppers pack twice the amount of vitamin C as green peppers.

DiCioccio says the research shows minimal effect if the cold or flu symptoms have already started, but chicken soup may help those who are already sick.

“If you’ve been feeling the symptoms for maybe a couple of days, chicken soup is what my mom always gave to me,” says DiCioccio. “The research shows comfort food makes you feel comfortable.”

Chicken soup’s healing powers are not only due to comfort though; DiCioccio says the soup itself is a good source of protein and the vapors can aid in reducing congestion.

The same can be said for tea, which has steamy decongestion properties as well.

Tea assists in reducing sore throats and boosting hydration, says DiCioccio. Mint or chamomile tea can help with upset stomach, but she warns to stay away from caffeinated teas.

“If you’ve already lost a lot of fluid you want to avoid caffeine, so you’re not getting more dehydrated.”

DiCioccio adds there are other foods rumored to prevent colds and flu that don’t have the research to support it.

“Garlic is on the list of things people think will help, but the research isn’t strong,” she says. “Things like echinacea, zinc— more research needs to be done and it needs to be more regulated.”

DiCioccio also warns against supplements and products that are not regulated by the Food and Drug Administration.

The best way to support immune health and prevent illness, she says, is to exercise regularly, get enough sleep, maintain a healthy, balanced diet, and stay hydrated.

“It’s not a guarantee, nutrition is never a guarantee in that sense, but it will help.”

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