How Drinking Tea May Inactivate COVID

New data published in Food and Environmental Virology shows that tea may be a useful COVID-19 prevention tool thanks to its ability to inactivate the virus in the mouth.

Although COVID enters the body primarily through the respiratory tract, it can also enter through the mouth. Once it does, its cells can replicate in the oral glands and mucosa before affecting other parts of the gastrointestinal system and additional body systems.

The new study shows tea may stop COVID in its tracks by reducing viral load upon contact, potentially helping reduce the spread of the virus both throughout the body and to other people.

The Virus-Fighting Properties of Tea

True teas, or teas made from the Camellia sinensis plant, include green, black, oolong, and white varieties. The plant polyphenols tea contains can reduce inflammation, potentially allowing the beverage to improve viral symptoms.

While earlier research suggesting a positive relationship between tea and COVID-19 prevention exists, the methodology used in these studies makes it hard to extrapolate the data to humans.

To fill the gap, researchers at the University of Georgia evaluated whether certain commercially available teas can quickly inactivate infectious SARS-CoV-2—the virus that causes COVID-19—in saliva. 

The researchers purchased 24 teas from multiple brands at the grocery store. Teas varied among leaves and types, including both true and herbal teas. Researchers steeped each tea in hot water for 15 minutes and prepared them at two concentrations: a standard steep and a highly concentrated version that people would be unlikely to drink.

Teas were then incubated with SARS-CoV-2 and assessed after five minutes.

When the tea was steeped at the concentration people typically enjoy, black tea showed the highest reduction in viral activity within 10 seconds of coming into contact with COVID. Green, Mint Medley, eucalyptus-mint, and Raspberry Zinger teas showed slight inactivation of COVID.

At the stronger concentrations, all varieties of tea showed a reduction in virus activity within 10 seconds.

The researchers attribute the effect to polyphenols.

Because the highest inhibitory effect of tea occurred in tandem with the moment of infection, if tea were to be used to help inactivate COVID in the real world, it probably has to be consumed as soon after infection as possible.

“Our results provide insights into a rapid at-home intervention (tea drinking or gargling) to reduce infectious SARS-CoV-2 load in the oral cavity which might also mitigate infection of the oral mucosa,” the study authors reported.

“To inactivate a virus is to make it non-infectious, meaning that it cannot infect the cells of the body. The tea infusions we identified inactivated the virus within 10 seconds,” study author Malak Esseili, PhD, Assistant Professor of Food Virology at the University of Georgia, told Verywell.

Malak emphasized that deactivating a virus in saliva is not a replacement for getting a vaccine.

“A vaccine works behind the scenes to make the immune system ready for the virus once it comes knocking on the door—when the virus invades the body through nose, mouth, or eyes,” she said. “Our study points to certain tea infusions that can kill the virus upon direct contact at one of these doors: the mouth.”

Should You Drink Tea If You Have COVID?

Whether tea is a must-have for infected individuals is yet to be determined.

“Our study was done in the laboratory on viruses in test tubes,” Malak said. “The virus continuously replicates, increasing in numbers at the entry sites such as nose or mouth, and it can move fast to the lung. That’s when we see severe disease. So, drinking or gargling with tea alone will not protect your lungs.”

While she added that tea on its own is not a sound COVID intervention and should not replace medical treatment, “picking a habit like drinking tea or gargling with it could be an additional intervention layer added to the known toolkit of intervention strategies.”

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.