It is best not to drink overnight soup. If the remaining soup is stored in aluminum and iron pots for a long time, harmful substances will settle. Do not drink the soup overnight and end the soup on the same day. If not, do not reheat it. Nitrites are very dangerous because reheating them can easily convert them into nitrites, a carcinogen.

The dangers of overnight meals are specifically:

1, the production of deadly nitrites: some overnight dishes can produce disease-causing nitrites. However, the nitrite content of overnight dishes will be determined by the temperature and storage time, so store overnight dishes in the refrigerator.

2, easy to be infected by bacteria: although the meal is heated and cooked, but there will be the presence of bacteria, the overnight meal is placed in the air, the bacteria will multiply, people again eat overnight meal is equal to eat bacteria, harmful to the body.

3, the decline in nutritional value: fried rice with the passage of time, its nutritional value also began to decline. In particular, the rice in the vitamin C is one of the most afraid of heat, is the hotter the less, if the rice has been repeatedly heated, the content of vitamin C is slowly lost, so, eat overnight meals did not add to the body's nutritional needs.

4, induced a variety of diseases: food contains nitrite, if nitrite into the human stomach, in a certain environment, it will be gradually converted into NC (N-nitroso compounds) of the material, this material is one of the factors that induced stomach cancer. Especially in the hot weather, overnight meals are easy to deteriorate, bacteria in the high temperature will be a large number of reproduction, it is easy to trigger gastroenteritis, resulting in food poisoning.