Steamed and pressed tea, commonly known as brick tea, is a semi-finished product made from various types of raw tea that has been sifted, fanned, cut, and ground. It is then steamed and pressed at high temperatures into brick-shaped or other types of tea cubes.

Brick tea includes rice bricks, Fu bricks, black bricks and flower bricks.

The appearance of rice brick tea is beautiful, the brick mold has sharp edges and corners, the pattern is clear and beautiful, the color is dark and lustrous, the inner soup is red and thick, the aroma is pure and the taste is mellow.

Black Brick Tea is in the shape of a rectangular brick with dimensions of 35*18*3.5cm. The brick surface is straight, the four corners are flat, and the mold pattern (trademark lettering) is clear. The color of the brick surface is dark brown, the internal aroma is pure, the taste is rich and slightly astringent, the soup is red-yellow and slightly dark, and the bottom of the leaves is old, tender and even. Each brick is 2kg net.

The manufacturing process of flower brick tea is basically the same as that of black brick.

Fu Brick Tea is rectangular in shape and 35*18.5*5 cm in size.

The products with larger output include Fu bricks, black bricks, flower tiles from Hunan and old green bricks from Xiangjian and Hubei. Kangzhuan, Jinjian, Fangbao from Sichuan, Jincha from Yunnan, and Liubao tea from Guangxi.

Brick tea is generally not made from the young leaves of tea, but from the old leaves. Brick tea has a higher fluoride content than other teas. The fluoride content of Ya'an brick tea is 543-586 mg per kilogram, and the brick tea produced in Yiyang is 365-400 mg per kilogram, which is dozens or hundreds of times that of green tea and scented tea.

Drinking large amounts of strong tea for a long time can cause accumulated fluorosis. The fluoride content in drinking water in ethnic minority areas is less than 1 mg/L, but the "brick tea" consumed by herdsmen has a fluoride content as high as about 1,000 mg/kg. Adult herders drink an average of 5 liters of water a day, most of which is milk tea and strong tea. Children also drink a lot of tea. A survey of 2,290 Mongolian children aged 8-12 found that 90.14% of the children suffered from dental fluorosis, and 10% suffered from severe dental fluorosis.

The incidence of osteoporosis among the Mongolian people who drink brick tea is 17% higher than that among the Han people. It can be seen that herdsmen's long-term drinking of strong tea and milk tea is the main cause of dental fluorosis, osteoporosis, waist and leg pain, etc.

In 1995, experts conducted an investigation into the fluorosis situation among Tibetan and Han people in Daofu County, Ganzi Tibetan Autonomous Prefecture. Investigations confirmed that the local water source contained low fluoride. However, Tibetan herdsmen and monks have been drinking brick tea in large quantities for a long time. The daily fluoride intake for adults is 12.46 mg, and for teenagers, it is 6.56 mg.

Tibetan herdsmen ingest too much fluoride, which can lead to chronic poisoning. Tibetans believe that if they drink too much brick tea or it is too strong, they will feel dizzy, numb in their hands and feet, convulsions, and joint pain in their limbs. Among local tea-loving Tibetans and teenagers, the incidence rates of skeletal fluorosis and dental fluorosis are as high as 73.5% and 51.2%. There was no case of skeletal fluorosis or dental fluorosis among the local Han adults and teenagers who did not have the habit of drinking brick tea.

According to calculations by experts, each Tibetan drinks an average of 10.77 kilograms of brick tea a year and 29.3 grams a day. Calculated based on the fluoride content of brick tea being 426 mg/kg, Tibetans can absorb 12.5 mg of fluoride by drinking brick tea every day, which is more than three times the safe dose.

So everyone should drink less