In the British, tea is "the liquid of health, as well as the drink of soul". In China, it is known as a "national drink". A lot of modern scientific researches have confirmed that, tea leaves do contain some biochemical ingredients which are closely related with human health. Tea leaves have a lot of pharmacological effects on human body, such as refreshing the mind and eliminating summer heat, promoting digestion and reducing phlegm, helping lose weight and relieving restlessness, promoting the secretion of saliva and slaking thirst, and so on. The pharmacological effects of tea leaves mainly come from tea polyphenol, caffeine, lipopolysaccharide, and so on. Specifically, the functions of tea are mainly as follows:

Firstly, tea can help slow down the aging process
Tea polyphenol has a strong oxidative stability and biological activity. It is a scavenger to clean the free radicals in human body. According to the relevant study, tea polyphenol can block the peroxidation of lipid, and clear away the active enzymes in the body, so as to play an anti-ageing effect. Result of experiment shows that, the anti-aging effect of tea polyphenol is 18 times higher than that of vitamin E.

Secondly, tea can help control cardiovascular diseases.
Tea polyphenol plays an important role in the metabolism of fat in human body. If there is too much cholesterol and triglyceride accumulating in the human body, it will cause the fat deposit on the blood vessel wall, thus leading to atheroma and other cardiovascular diseases. Research points out that, tea polyphenol can inhibit the hyperplasia of maculosus, reduce the fibrinogen that may increase the viscosity of blood clots, so as to inhibit cardiovascular diseases.

Thirdly, tea can help prevent and fight against cancer.
Tea polyphenol can block the synthesis of various kinds of carcinogenic substances in the body, such as ammonium nitrate. What's more, it also has the effect to directly kill the cancer cells and improve the immunity of human body. According to the data, it is shown that tea polyphenol (mainly catechin compounds) is very beneficial for the prevention and auxiliary treatment of stomach cancer, colon cancer, and many other kinds of cancer.

Fourthly, tea can help prevent and treat the damage caused by radiation.
Tea polyphenol and its oxidative products have the ability to absorb the toxicity of radioactive substances, such as strontium 90 and cobalt 60. According to the clinical trials from relative medical department, it is confirmed that tea extracts can effectively treat mild radiation sickness during the therapeutic process, and the efficiency can reach more than 90%. In addition, tea extracts are also very effective in the treatment of cytopenia and leucopenia caused by radiation.

Fifthly, tea can help inhibit and resist virus and bacteria.
Tea polyphenol has a strong astringent ability, and it plays an obvious effect in controlling and killing pathogenic bacteria and virus. At the same time, tea can also effectively diminish inflammation and eliminate diarrhea. In traditional Chinese medicine, tea leaves are often widely used in the treatment of acute and chronic dysentery, amebic dysentery, influenza, and so on, and the efficiency is up to 90% or so.

Sixthly, tea can help beautify and care the skin.
Tea polyphenol is a kind of water-soluble substance. If you use tea leaves to wash the face, it can remove the fat on the face and astringe the pores. In addition, it also has a lot of effects on the skin, such as disinfection, sterilization, and slowing down the process of skin aging. At the same time, it can also reduce the damage on the skin caused by ultraviolet radiation in the sunlight.