In order to save water, some people often reheat the leftover boiling water, which is a bad habit. Because repeated boiling water will cause water aging, it will not only lose minerals beneficial to human body, but also produce some harmful substances such as nitrite. Once nitrite enters the human body in large quantities, it can make the red blood cells in the blood lose their oxygen-carrying function and lead to tissue hypoxia. People who drink this water for a long time will have symptoms such as nausea, vomiting, headache, purple nails and lips, and palpitation. It may even cause hypoxia and even induce cancer.
A cold drink after getting up in the morning is good for your health. Many people like to dry a cup of boiled water the night before and drink it the next morning. This practice is possible in the case of low temperature; For example, in summer, when the temperature exceeds 30 degrees Celsius, the air humidity is high, and bacteria multiply rapidly, cold boiled water will lose its biological activity overnight, which is easy to be polluted and cause diarrhea. You can pour half a cup of boiling water the night before, then cover it and drink it with warm water the next morning.
In addition, don't leave cold boiled water for too long. It is best to drink boiled water on the same day. It is best not to drink cold boiled water for more than 3 days.