Tea has always been regarded as a product to prolong life and is known as "the emperor in oriental drinks". The expression "seven things to open the door" (firewood, rice, oil, salt, sauce, vinegar and tea) includes tea, which shows the importance of tea in a day. Tea is a low-calorie food. Generally, the better the quality of tea, the higher the heat energy. In terms of types, green tea has the highest calorie. The water-soluble vitamins contained in tea can be dissolved in hot water, so drinking tea can supplement many vitamins needed by human body. In addition, tea is refreshing because it contains caffeine, which has the function of exciting the central nervous system. Tea leaves are brewed with boiling water, and fat-soluble nutrients are difficult to be absorbed and utilized. Therefore, it is advocated to eat tea properly to make up for this defect, that is, to make tea into ultrafine powder and add it to various foods, such as tea tofu, tea-containing noodles, tea-containing ice cream and so on. After eating these tea foods, you can get fat-soluble vitamins contained in tea and give full play to the nutritional value of tea. In addition, there are many tea drinks on the market, and the new national standard is that the content of tea polyphenols can only be regarded as tea drinks, not tea-flavored drinks, so you should choose carefully.