Boiled eggs in the shell can be eaten overnight if they have not deteriorated, but it is not recommended. It is still recommended to eat boiled eggs in shell on the same day. If you accidentally eat spoiled eggs or eggs taken out of the refrigerator without heating may lead to gastrointestinal discomfort such as diarrhea, abdominal pain, nausea, vomiting and other symptoms. Whether overnight boiled eggs will deteriorate depends on storage conditions and cooking methods. If the uneaten eggs are not put in the refrigerator, they will deteriorate more easily and may cause discomfort after consumption. In addition, if the egg is not fully cooked and is a loose egg, the yolk will be more likely to harbor bacteria, so overnight eating is not recommended in this case. Whether it is an overnight boiled egg in the shell or other overnight food, if it has not deteriorated and you are worried about wasting food, it is recommended that it be fully heated before consumption. If you are worried about wasting food, you can eat and make as much as you want later to avoid leftovers and food left overnight. If you cook too many eggs at once and fail to finish them, you can put the remaining eggs directly into the refrigerator. It is recommended that you use a fresh box or plastic bag to store them in a sealed container and consume them as soon as possible. Be sure to heat them sufficiently before consumption.