I. The hazards of overnight tea:

1. Tea contains tea polyphenols, which are very easy to oxidize in the air and water into a brown colloid, which is the tea rust. Tea rust contains pickaxe, lead, arsenic, mercury and many other substances. Overnight tea water exposed to the air the longer the tea polyphenols oxidized into the amount of tea rust is also more. Tea rust into the human body, and food in the protein, fat and vitamins, such as combining, precipitation, it will hinder the absorption of nutrients and digestion.

2. Once these oxidized substances enter the body, they can also cause inflammation, necrosis and other lesions in organs such as the kidneys, liver and stomach. Therefore, overnight tea water can not be drunk, and tea utensils should be frequently scrubbed.

3. Summer temperature is high, tea is easy to deteriorate, if shelved for more than 24 hours, it is best not to drink, some of the resistance to weaken the elderly, it is easy to cause diarrhea.

4. Overnight tea water because of the time is too long, most of the vitamins have been lost, and tea in the protein, sugar, etc. become bacteria, mold reproduction nutrients, so that should not drink.

II. Overnight tea a false perception

Drinking overnight tea water will cause cancer, this statement is not correct, long placed in the tea, will produce nitrites, but nitrites itself is not carcinogenic, only nitrites into the human body and the role of gastric acid, the formation of nitrosamines, is a strong carcinogen, closely related to the occurrence of liver cancer and other diseases.

And the nitrite content within a certain range is a safe dose, overnight tea produced by the nitrite content does not exceed the unit of this safe dose, which also shows that the overnight tea water will cause cancer is actually wrong.