Tea polyphenols are also called tea tannins or tea boots. They belong to polyphenols and are one of the main chemical components in Gunpowder Green Tea. They account for 20% to 35% of the total dry matter of tea. Tea polyphenols are a complex composed of more than 30 phenolic substances, mainly including catechins, flavonoids, anthocyanins and several phenolic acids. Among them, the content of catechin is the most, accounting for more than 70% of polyphenols.

The chemical properties of tea polyphenols are different from tannins or tannins (commodity), and they are also different from tannins in other plants or fruits. It does not cause reactions that are not conducive to the stomach; although it and protein also work, but Unlike other polyphenols, it has a strong reversible reaction. Medical studies in many countries have proved the efficacy and effects of tea polyphenols and their pharmacological value on the human body.

Tea polyphenols have the effect of enhancing the activity of capillaries
　　Tea polyphenols can enhance the activity of capillaries, reduce the permeability of capillaries, and improve their resistance to vascular rupture. Medical experts in the former Soviet Union and India have measured the degree of bleeding caused by the decompression method in rats, and proved that the tea polyphenols of green tea can reversibly improve the strength of capillaries. After cutting off the supply of vitamin P to the rats for two or three weeks, they then took 0.01 mg of tea polyphenols. As a result, the fragility of the capillary wall was reduced. If a large dose of 1 mg is taken, there will be significant results after 3 hours. If guinea pigs are given green tea soup or tea polyphenols, the stability of capillaries against rupture is significantly improved under vacuum conditions within two weeks.

　　 A mixture of tea polyphenols and vitamin C was tried on the human body. The effect of strengthening the capillary wall was doubled compared with the control group taking vitamin C alone.

　　 In addition, the flavonols found in the separation of tea polyphenols by Green Tea Factory have the effect of strengthening blood vessels and are now used as a medicine for the treatment of high blood pressure.