Recently, the claim that "overnight food is carcinogenic" has been all the rage. So, is there any truth to this? Wang Xingguo, a standing director of the Dalian Nutrition Society, told a reporter from the Life Times that prolonged storage does indeed increase the toxic components in food.
Five types of overnight food you should never eat
"Overnight food" doesn't just refer to dishes left for a whole night. Any food that has been stored for more than 8-10 hours should be considered as such. The increase in toxic components in food is due to two reasons. First, chemical substances in the food produce carcinogens, such as nitrites, which cannot be removed even by reheating. The second reason is secondary contamination from external bacteria during storage. The following types of dishes are particularly harmful when left for a long time.
Green leafy vegetables are the most dangerous when left overnight. Generally, stem and leafy vegetables have the highest nitrate content, followed by gourds, with root vegetables and cauliflower-like vegetables in the middle. Therefore, if you buy a large quantity of vegetables, you should eat the leafy ones first, such as Chinese cabbage and spinach. If you plan to cook extra food to reheat the next day, you should try to make fewer stem and leafy vegetables and choose gourds instead.
Overnight seafood can damage the liver and kidneys. Seafood such as crabs, fish, and shrimp will produce protein degradation products after being left overnight, which can damage liver and kidney function. If you have bought too much, you can store raw seafood in a sealed bag or container and freeze it for cooking later. Semi-cooked eggs can easily cause illness. Many people love soft-boiled eggs with runny yolks, but these eggs are not thoroughly sterilized. Coupled with the fact that eggs are rich in nutrients, they are particularly prone to bacterial growth, which can be dangerous to consume. If the eggs are fully cooked and stored properly at low temperatures in a sealed container, it is fine to eat them the next day. Be careful with silver ear mushrooms and other fungi. Whether wild or cultivated, fungi like silver ear mushrooms and mushrooms tend to retain a lot of nitrates. If they have been stored for a really long time, you may have to throw them away.
Don't store soup in metal containers. Making soup is time-consuming and laborious, so people often make a large pot that lasts for several days. If leftover soup is kept in an aluminum or iron pot for a long time, harmful substances can leach into it. The best way to store soup is to not add salt or other seasonings until you are ready to eat it. After cooking the soup, use a clean spoon to serve the portion you plan to drink that day. For the leftovers, it's best to store them in a clay pot or a sealed container in the refrigerator.