This Is What You Should Drink If You Feel a Cold Coming on, According to Science

The colder seasons are upon us, and that means so many wonderful things: falling leaves, cozy sweaters, crackling fireplaces, and the holidays. But, unfortunately, it also means flu season.

When your body begins showing signs of a nasty cold, like sneezing or congestion, or a whole body flu, like chills and fatigue, you might be inclined to hurry to the drugstore or your medicine cabinet to take over-the-counter meds—which may or may not work. But too often we forget about nature’s remedies for fighting the flu.

Turns out, sipping a hot cup of tea is not only comforting while you’re feeling under the weather, but according to research, it’s chock-full of benefits to help you combat this season’s biggest sickness.

According to research published in the Proceedings of the National Academy of Sciences, drinking black tea is a major immune booster. The study, out of Brigham and Women’s Hospital in Boston and Harvard Medical School, found that people who drank five cups of black tea a day for two weeks saw their immune system T cells pumping out 10 times more cold and flu virus-fighting interferon.

“We worked out the molecular aspects of this tea component in the test tube and then tested it on a small number of people to see if it actually worked in human beings,” explained Jack F. Bukowski, MD, one of the study’s researchers. According to Dr. Bukowski, the results are proof that five cups of tea a day can enhance the body’s disease defenses.  

Green tea is another noteworthy flu-fighter thanks to its antioxidant quercetin, as well as an amino acid called L-theanine. Various studies have shown that quercetin acts as a potent antiviral agent, hindering viral replication of many respiratory viruses, including influenza virus. One study, published in the Journal of Medicinal Food found quercetin to inhibit the replication of a common cold virus in its initial stage of infection.

A study completed by researchers at University of Florida and the Nutritional Science Research Institute and published in the Journal of the American College of Nutrition found that L-theanine and decaffeinated green tea catechins are capable of boosting the body’s immune system. The results suggest that green tea can decrease the incidence and duration of cold and flu symptoms.

“With this study, we were able to show that ingestion of a specific combination of decaffeinated tea polyphenols standardized to 45 percent EGCg and L-theanine, would enhance systemic immunity, and prevent cold and flu symptoms in healthy individuals. This is a significant finding,” said lead study author Susan S. Percival, PhD.

The benefits of tea have long been accounted for, but it is easy to forget that a soothing cup does more than just satisfy you—it can prevent against pesky, and sometimes life-threatening, viruses like the flu.