Long-term eating leftovers is harmful to the body's nutritional balance and digestive system function. The nutrients contained in leftovers will be greatly reduced, eating these things and eating fresh food nutrition is not comparable. In addition, leftovers are also prone to harbor bacteria and carcinogens, and the nitrite content of these foods is significantly higher than that of fresh foods, which increases the risk of cancer when eaten over a long period of time. Breeding bacteria can easily lead to gastroenteritis and intestinal flora imbalance induced Helicobacter pylori infection, which in turn causes a series of digestive diseases. Many people in order to prevent waste tend to put this meal to the next meal, microwave heating after eating or put into the refrigerator, the next meal hot and then eat is not right, because long-term eating leftovers, leftovers have a great harm to the body, for example, there will be the symptoms of acute gastroenteritis, because long-term put the meal is prone to deterioration and thus produce bacteria, eaten after nausea, vomiting and diarrhea symptoms. Long-term eating leftovers, leftovers will lead to an increase in nitrite content in the body, which will lead to the risk of cancer, so it is recommended or not to eat leftovers and leftovers for a long time, it will be a great help to the human body.