Tea is an anticancer agent

The anticancer effects of tea have been reviewed. It is estimated that more than 20 laboratories in several countries have reported the anticancer effects of tea extracts and tea polyphenols on different organs in animal experiments. Tea broth with 1.25 g of green tea plus 100 mL of boiling water as the only beverage for mice reduced chemical carcinogen-induced lung tumors in mice by 36% to 44% and reduced tumor multiplication by 44% to 60%. Decaffeinated tea and black tea had the same effect. In addition, treating animals with green or black tea can reduce esophageal, stomach or skin cancer in experimental animals by 70%.
Studies have also shown that the anticancer activity of tea can be best achieved by feeding green or black tea at least two weeks before treatment with carcinogens and continuing until one week after treatment with carcinogens. Epidemiologic investigations have shown that people who drink more tea have a lower risk of stomach cancer. In the past, it was believed that the reports that tea consumption would increase the incidence of esophageal cancer were caused by drinking hot tea, such as drinking normal temperature tea can also reduce the incidence of esophageal cancer. The study on the effective dose of tea drinking against cancer shows that when hamsters drink 2 to 3 cups of tea, the tea polyphenol content in the blood is equivalent to the concentration of the effective dose in the anti-cancer experiment.
The anti-cancer mechanisms of tea are as follows:
① antioxidant activity of tea polyphenols;
② Tea polyphenols inhibit the activity of enzymes (ornithine decarboxylase, protein kinase C, lipoxygenase and cyclooxygenase) that have a tumor-promoting effect;
(iii) Tea polyphenols promote the activity of enzymes with anticancer activity (glutathione peroxidase, catalase, glutathione-S-transferase, NADPH-quinone oxidoreductase, uridine diphosphoglucuronosyltransferase, and methoxy-9-hydroxyisophene D149 azole-O-dealkylase);
④Immunity-enhancing;
⑤ Anti-tumor proliferative activity.