This morning, my colleague, Aqiang, grabbed a large pot of tea and started drinking it non-stop.
"Why the sudden urge to drink tea?" Xiaoi asked, surprised. Aqiang was usually not a tea lover.
"Well, more and more people are testing positive for COVID-19, and I heard tea not only prevents cancer but also helps fight the virus, so I’m drinking more."
...But after drinking too much tea, Aqiang spent the entire morning running to the bathroom.
Tea is an ancient Chinese beverage. There have been claims that tea can prevent and even fight cancer, and during the pandemic, tea was also said to help kill the COVID-19 virus. But is this true?
A research team from Nara Medical University in Japan conducted a study where they tested around 10 types of tea, including green tea, black tea, and the local "Yamato tea." They mixed these teas with a liquid containing the COVID-19 virus and observed the virus levels. The result showed that black tea was the most effective in neutralizing the virus—after 1 minute, it killed 99% of the virus, and after 10 minutes, the virus count dropped by 99.99%.
The question is: can drinking tea in daily life prevent COVID-19 infections?
It’s important to note that the results from laboratory tests do not necessarily apply to the human body. Tea enters the digestive system, not the lungs. Dr. Zhong Wu, a researcher at the National Emergency Drug Engineering Center, stated that there is currently no evidence that drinking tea can prevent or treat COVID-19. To avoid infection, proper personal protective measures are still necessary.
The researchers themselves concluded, "This study did not verify that drinking tea can prevent COVID-19 infection."
Researchers from the University of Milan conducted a meta-analysis of 22 studies involving nearly 30,000 participants (9,438 with stomach cancer and 20,451 without). The study found that, compared to non-tea drinkers, regular tea drinkers had a 0.91 reduced risk of developing stomach cancer. Specifically, those who drank 1–2 cups of tea a day had a risk ratio of 1.01, while those who drank 3 or more cups per day had a 0.91 risk ratio.
In other words, drinking tea is associated with a lower risk of stomach cancer.
Why do many studies suggest that tea can fight cancer? This is mainly due to the presence of polyphenols, particularly epigallocatechin gallate (EGCG), which have been shown to have anti-cancer effects in epidemiological studies, cell cultures, animal experiments, and clinical trials.
But can drinking tea directly lower cancer risk? The answer is no. Despite many studies supporting the anti-cancer properties of tea, there is still insufficient evidence to confirm its direct impact on human health. Moreover, the amount of polyphenols in tea is relatively small, so while polyphenols may have some anti-cancer potential, drinking tea alone is not enough to prevent cancer. It’s important to maintain a balanced view on this matter.
While tea may not directly prevent cancer, it is undoubtedly a healthy beverage with several benefits. Tea contains over 450 organic compounds and more than 15 inorganic minerals, such as polyphenols, catechins, amino acids, and vitamins. Drinking tea regularly can offer several health benefits:
Boosts Alertness: Tea contains caffeine, which stimulates the central nervous system, helping to reduce fatigue and improve concentration and memory.
Aids Digestion: The vitamins and caffeine in tea can increase stomach acid production, promoting digestion.
Acts as a Diuretic: Tea stimulates kidney function, helping to expel urine more quickly and remove harmful substances from the body.
Helps Warm the Body: Tea can help dispel cold from the body, warming you up and providing a comforting effect during cold weather.
The National Health Commission of China suggests that individuals with COVID-19 or those recovering from it should drink 1.5–2 liters of water or mild tea each day.
While drinking tea offers health benefits, it’s important to be mindful of how much and when you drink it. Here are three key guidelines:
Drink in Moderation: Avoid drinking overly strong tea. Typically, 3 grams of tea per cup is enough. Aim for around 8–10 cups of tea per day.
Watch the Timing: Avoid drinking tea during meals, as the polyphenols in tea can interfere with the absorption of iron from food. It’s also best not to drink tea right before bed, as the caffeine content can interfere with sleep.
Avoid Drinking Tea Too Hot: Drinking tea that is too hot can increase the risk of esophageal cancer. Studies have shown that people who regularly drink tea at temperatures above 60°C have a 41% higher risk of esophageal cancer compared to those who drink tea at lower temperatures.
In conclusion, while drinking tea can provide health benefits, such as boosting alertness, aiding digestion, and providing antioxidants, it is not a cure for cancer, nor does it directly prevent cancer or viral infections like COVID-19. Enjoy tea in moderation, and remember that maintaining a balanced lifestyle and following proper health guidelines is the best approach to overall wellness.
