Steamed steamed bread with porridge

We don't have the habit of cooking porridge and steaming steamed bread at home, and we don't know that people around us have such a habit. If someone does this, it is estimated that it will not hurt the body. The bottom water is not suitable for drinking, because pure water will turn into nitrite after boiling for a long time. With the increase of boiling time, the water content decreases and the nitrite concentration increases, which has carcinogenic effect. Drinking this kind of water often is easy to get gastrointestinal diseases and premature aging. Cooking porridge is different. Porridge water contains a lot of hydroxyl and hydrogen ions, and nitrate is very stable in this environment, or it is oxidized into nitrate when nitrate is converted into nitrite, so cooking porridge will not be harmful to nitrite.