After repeated heating, water is called thousand boiling water, which contains a lot of nitrite. After drinking, there will be symptoms such as hypoxia and dizziness, mainly because after repeated boiling, the water will evaporate, but harmful substances will slowly accumulate and become more. Therefore, don't boil the unfinished water in life, which is harmful to the body.
We all know that water cannot be heated repeatedly, but we know only a little about why it cannot be heated repeatedly and what harm it will do after repeated heating. Generally speaking, boiled water after repeated heating is called thousand boiling water, which contains a large amount of nitrite. This chemical will affect the function of blood carrying oxygen, resulting in adverse reactions such as hypoxia, dizziness and nausea.
In short, the water actually contains some harmful substances. After repeated boiling, the water will gradually evaporate, but the harmful substances that are not easy to volatilize will remain, and the concentration will slowly increase. People will naturally be harmful after drinking.
Although it is a kind of economical behavior for many people to heat the unfinished water before drinking it, this behavior is unnecessary. Although it avoids the waste of water to a certain extent, it will be harmful to their health. Therefore, it is recommended to burn enough water every time.