However, in recent years, there have been a number of myths that claim that overnight food will not have a negative health impact as long as the food is properly preserved.
In fact, misconceptions about overnight foods are prevalent among the general public, and today, we're going to dive into this issue to help you understand which overnight foods are safe and which are not suitable for consumption.
I hope that through this article, we will unravel the mystery of overnight food for everyone, so that everyone can eat with peace of mind and live a healthy life.
In fact, the harm of overnight food is not entirely caused by the night, and food left out for a long time, whether during the day or at night, will lead to the proliferation of microorganisms.
These microorganisms can release some harmful substances during the reproduction process, or cause the food to become moldy and spoiled. Therefore, the concept of overnight food is less about time and more dependent on how and under conditions the food is kept.
So, what is overnight food?Generally speaking, if the food has been left for 5 to 8 hours from the time the cooking is completed, it can be considered overnight food.
However, this does not mean that overnight food is necessarily harmful to the body, as long as the food is stored properly and there are no problems such as mold and spoilage, it can still be eaten even if it has been left overnight.
Of course, the freshness and nutritional value of food gradually decreases during the placement process, therefore, we should minimize the storage time of food, especially for those foods that are prone to spoilage. 
Nutritional value decreases
Overnight foods can be refrigerated or heated, and nutrients in them may be lost, and certain vitamins and enzymes are easily broken down during storage and heating, resulting in a decrease in the nutritional value of the food.
Food spoilage
When food is stored at room temperature for too long, bacteria and other microorganisms can grow and cause food spoilage, and these microorganisms can produce harmful toxins and have a potential risk of food poisoning, leading to gastrointestinal upset and digestive problems.
Increase harmful substances in food
Certain chemicals in overnight food may accumulate during storage and reheating, for example, foods that have been heated multiple times may produce carcinogens, such as polycyclic aromatic hydrocarbons.
Indigestion and gastrointestinal upset
Refrigerated and heated foods may cause indigestion and gastrointestinal upset, which may be due to reduced bacterial and enzyme activity in the food, affecting the digestion and absorption of the food.
Overnight meat
Meat ** is relatively expensive, and it often makes people feel that it is a pity to throw it away, so can you eat overnight meat?Generally, meat is safe to eat after being stored overnight and as long as it is handled properly.
Although there may be some loss of B vitamins, it will not cause significant damage to the human body, and although there will be some differences in taste during the reheating process, overall, overnight meat is still nutritious and delicious.
However, the situation is different when it comes to foods such as fish and seafood, where the nutrients tend to encourage bacteria to multiply, and they often take a short cooking time to maintain their delicious taste, which can lead to bacterial blooms. Overnight water
In our daily lives, there is a common belief that "overnight water cannot be drunk" and "overnight water is toxic", which has been widely circulated for many years, however, according to relevant research, there is no scientific basis for this statement.
Overnight water refers to water that has been left in a sealed state overnight, in which case the bacterial content and nitrite content of the water have changed very little and are negligible, and from a scientific point of view, the overnight water has not changed much and is still drinkable.
Some people think that overnight water is poisonous, this view is even more nonsense, toxins do not appear out of thin air, but need a certain amount of chemicals and bacteria and other microorganisms to react to produce, as long as the water source is clean, and the water has been thoroughly boiled, then the water is safe, and will not produce toxic substances. Overnight dishes
Some overnight dishes can be eaten with confidence, but some will pose a certain threat to human health, such as overnight white fungus and mushrooms, which belong to saprophytic foods, and a large amount of nitrates will accumulate on the surface and roots, which are easy to spoil after being left for a long time, so they should be eaten as soon as possible.
Don't eat leafy greens overnight, because the rhizomes of leafy greens contain a lot of nitrates and vitamins, and after secondary heating, a large amount of nitrates will be released, which is harmful to the health of the intestines.
In order to maintain health, we should pay attention to the way the food is kept and the time it is consumed, for overnight dishes, we should judge whether it can be eaten according to the situation, generally speaking, cooked vegetables are more likely to spoil than raw vegetables, so cooked vegetables that are cooked overnight should be eaten with caution, and raw vegetables, such as lettuce, kale, etc., can be eaten with confidence after being washed and processed.
Overnight eggs
Whether an overnight egg is edible or not depends mainly on how the egg is cooked, and for some specific cooking methods, such as soft-boiled eggs, we do not recommend that you eat them overnight.
In the case of soft-boiled egg products like sugar eggs, which are not fully cooked eggs, these substances react with oxygen in the air after being left out for a while, due to the fact that some of the proteins and sugars inside are not completely denatured, causing bacteria to grow.
If such eggs are consumed, it may cause gastrointestinal upset and even trigger health problems such as diarrhea, however, for some eggs that have been fully cooked, such as boiled or steamed eggs, it is possible to eat them overnight because all the substances inside them have been denatured, and bacteria cannot grow and multiply in them.
Rapid cooling
Quickly cool cooked food to room temperature and put it in the refrigerator as soon as possible, cutting large pieces of food into smaller pieces can speed up the cooling.
Use an airtight container
Store overnight food in clean, airtight containers to prevent contamination by bacteria and other microorganisms, choose appropriately sized containers so that the food is fully exposed to cold air.
Marking and Description
Mark the name of the food and the date of storage on the container to make it easier to track and avoid excessive storage.
Refrigerate or freeze
Store overnight food in a cold area of the refrigerator (usually 2-4 degrees Celsius), and the refrigeration time should generally not exceed 2-3 days.
If it needs to be stored for a long time, the food can be divided into portions and stored in a freezer bag or container with an airtight freezer bag.
Look at the freshness of the food and how it is preserved
Generally speaking, if the food can be kept relatively airtight and refrigerated during the preservation process, then its freshness will be guaranteed to a certain extent.
However, if the food is not well preserved, such as left open or kept at room temperature, then the food is susceptible to contamination by bacteria and microorganisms, making it unsafe.
Look at the type of food
Some foods are inherently prone to bacteria and microorganisms, such as cooked food, meat, fish, etc., which are prone to spoilage even when stored at low temperatures.
Some vegetables and fruits have a relatively short shelf life, but if they can be kept dry and sealed during the preservation process, then their freshness can also be guaranteed to a certain extent.
It depends on the physical condition of the individual
For some people with poor immunity, consuming overnight foods may pose some health risks. Therefore, this group of people should try to avoid overnight food, especially if it is not well preserved.