Get up in the morning, don't drink tea on an empty stomach immediately. Because tea contains caffeine and other alkaloids, drinking tea on an empty stomach can easily make the intestines absorb too much caffeine, which will cause some people to have symptoms of temporary adrenal cortex hyperfunction, such as palpitation, dizziness, weakness of hands and feet, and trance. People who don't drink tea often, especially those who drink strong tea on an empty stomach in the morning, are more likely to have the above symptoms. This is medically called drunk. Once you get drunk, you just need to have a sugar in your mouth or drink some sugar water to relieve it.

Middle-aged and elderly people with gastric and duodenal ulcers should not drink tea on an empty stomach in the morning, especially strong tea. Because too much tannic acid will stimulate gastrointestinal mucosa, aggravate the condition, and some will have indigestion or constipation.

In addition, most tea leaves contain fluoride, and drinking tea on an empty stomach can easily lead to excessive fluoride intake. If fluoride accumulates too much in human body, it may cause intestinal diseases, weaken muscle elasticity, damage life function, damage teeth and even have toxic effects on bones. According to the determination, brick tea leached 0.25 mg of fluorine per gram, while tender tea only leached 0.06 mg of fluorine per gram. Under normal circumstances, using 3 to 10g of tea every day, according to the above data, obviously will not increase excessive fluoride in the human body. But drinking tea on an empty stomach in the morning, especially strong tea, may lead to chronic fluorosis for a long time, causing the above symptoms.