Just mentioning dark tea might seem unfamiliar to some, but when it comes to Pu'er, almost everyone knows it. Pu'er tea is the most representative type of dark tea. In addition, the well-known oolong tea, although sometimes categorized separately as its own type, can also be essentially considered dark tea based on its fermentation type and appearance.

Promoting digestion and resolving food stagnation can be regarded as the health function of dark tea. In Chapter 63 of Dream of the Red Chamber, after Baoyu had eaten too many longevity noodles on his birthday, he dared not go to bed immediately. The housekeeper instructed a maid to bring Baoyu a bowl of Pu'er tea, and Baoyu's close maid Xiren immediately said, "I have brewed a cup of Daughter tea."

Daughter tea is a milder type of Pu'er, which can aid digestion and has a much lower caffeine content than green tea, so drinking some in the evening does not cause worry about sleeplessness. In addition, dark tea can also cut through grease. Ethnic minorities in border regions who live on beef and mutton regard dark tea as the tea of life.

In winter, people not only have an increased appetite but also tend to store substances in the body, making them prone to weight gain. For modern people who eat a lot of meat and rich food, drinking more dark tea can not only eliminate greasiness but also cleanse blood lipids, protect blood vessels, and prevent obesity.

Generally, the first three infusions of dark tea are considered the best. However, since the tea leaves are often aged, you can quickly rinse them with boiling water before brewing to remove any impurities. On weekdays, drink one cup every 1–2 hours on average before 4:00 PM, and drink less in the evening.

Although dark tea aids digestion, all teas contain tannic acid, which can combine with protein to form precipitates, affecting protein absorption and interfering with gastrointestinal motility, potentially causing constipation. Therefore, it is not advisable to drink it immediately after meals; it is best to wait an hour.