It is best not to drink overnight soup. If the remaining soup is stored in aluminum pot and iron pots for a long time, harmful substances will precipitate. Don't drink soup overnight, end the soup on the same day. If not, please do not heat it again. Nitrite is very dangerous because it can be easily converted into carcinogen nitrite after reheating.

The hazards of overnight meals are as follows:

1, Production of deadly nitrite: Some overnight dishes will produce pathogenic nitrite. However, the nitrite content of overnight dishes will be determined according to the temperature and storage time, so overnight dishes should be kept in the refrigerator.

2, easy to be infected by bacteria: although food is cooked by heating, there will be bacteria. If you put overnight meals in the air, bacteria will multiply. People eat overnight meals again, which is equivalent to eating bacteria and endangering their health.

3. Decline in nutritional value: With the passage of time, the nutritional value of cooked food began to decline. Especially vitamin C in meals is the most afraid of heat, but the hotter it is, the less it is. If the food is heated repeatedly, the content of vitamin C will be gradually lost, so eating overnight meals can not supplement the nutrition needed by the human body.

4, induce various diseases: food contains nitrite, if nitrite enters the human stomach, under certain circumstances, it will gradually transform into NC(N- nitroso compound), which is one of the factors that induce gastric cancer. Especially when the weather is hot, overnight meals are easy to deteriorate, and bacteria will multiply in large numbers at high temperature, which will easily lead to gastroenteritis and food poisoning.