Eggs are certainly nutritious, but if you eat the wrong way, not only no nutrition, but also harmful, eggs must be cooked and can not eat raw. Raw eggs are not only no benefit to the human body, but also some of the following adverse effects: 1. Eat raw eggs easy to get biotin (biotin) deficiency This is because the raw egg white contains a harmful to the human body known as the proximate element (avidin) protein. This protein in the intestinal tract and biotin and other tightly bound, become a stable and inactive complex, thus hindering the absorption of biotin. Biotin is a water-soluble vitamin that is a coenzyme of carboxylase in the body and is involved in carbon dioxide fixation and carboxylation reactions. If a large amount of raw egg white is ingested, one may suffer from biotin deficiency, which manifests itself as generalized weakness, sensory hypersensitivity, dermatophytic dermatitis, loss of scaly epithelial cells on the lips, flaking and other symptoms. If the heating process, the egg white of this proximate element that is destroyed, no longer have the role of hindering the absorption of biotin. 2. Eat raw eggs, the protein is not easy to digest and absorb because the protein structure of raw eggs dense, in the gastrointestinal tract is not easy to be hydrolyzed by protein hydrolysis enzymes. Raw eggs contain a kind of antitrypsin, can inhibit the hydrolysis of food protein by trypsin. In addition, raw eggs are a semi-fluid mucus-like object with a short residence time in the gastrointestinal tract. Most of the protein and other nutrients in raw eggs are wasted due to incomplete digestion and absorption. Eggs after heating, the original structure of dense proteins, due to the molecules within certain non-***valent chemical bonds, such as hydrogen bonds, salt bonds, hydrophobic bonds, etc. fracture, the structure has become loose and irregular, that is, the protein denaturation, which is conducive to the protein hydrolase catalytic hydrolysis. At the same time, and because of the heat denaturation of antitrypsin, it will no longer inhibit trypsin. The latter can make all kinds of molecular proteins digested into small molecules of peptides, and even amino acids and be absorbed and utilized. 3. Eat raw eggs can increase the burden on the liver A large number of undigested proteins in the lower part of the large intestine by the role of Escherichia coli and the occurrence of corruption, resulting in a greater number of toxic substances, such as amines, phenols, ammonia, indole, hydrogen sulfide and so on. Although some of these toxic substances are discharged from the body with feces, but there is still a considerable part of the intestinal tract is absorbed, through the portal vein into the liver, by the liver for detoxification. If the person who eats raw eggs originally has liver function damage, then due to the increased burden on the liver and poisoning may occur, headache, dizziness, and even blood pressure drop or rise and other symptoms. When eggs are cooked and eaten, usually about 95% of the protein may be digested and absorbed. In this way, the toxic substances produced in the large intestine is greatly reduced, the burden on the liver is relatively reduced. 4. Eat raw eggs easy to get intestinal inflammation Egg shell, the naked eye looks almost impermeable, does not allow anything to pass. But under the microscope, the shell is full of small holes, the pore size than the pathogenic bacteria dozens or even hundreds of times. Therefore, it is inevitable that some pathogens (e.g. salmonella, etc.) will invade the egg after it is laid. If you eat raw eggs contaminated by pathogens, acute gastroenteritis may occur, manifested as chills and fever, nausea and vomiting, abdominal pain and diarrhea. Eggs after burning hot, the pathogen has been killed, there will be no gastrointestinal symptoms. 5. Eat raw eggs can cause loss of appetite and indigestion This is because raw eggs have a special fishy flavor, this fishy flavor can inhibit the central nervous system, so that the secretion of digestive juices to reduce. Despite eating raw eggs have so many adverse effects, but now eat raw eggs are still not lack of people. According to the author of the school 220 first-year secondary school students survey, found that eating raw eggs competition up to 36%. This ratio can not be ignored. Analyze the reason, mainly because these young students do not understand the knowledge of nutritional hygiene. Some students also wrongly believe that eating raw eggs than eating cooked eggs better nutrition. In view of this situation, the author suggests, as teachers, especially primary and secondary school teachers, it is very necessary in the classroom, or through the blackboard newspaper and the form of science lectures, to publicize to young students that eggs can not be eaten raw. Students understand these reasons, you can do not only their own no longer eat raw eggs, but also to the family and others to make extensive publicity, to popularize the knowledge of nutrition and health, which is undoubtedly a very useful thing. Raw egg protein structure dense, gastrointestinal digestive enzymes are difficult to contact, and therefore not easy to be digested and absorbed. Cooked egg protein structure becomes fluffy, easy to be digested and absorbed by the human body. About 10% of fresh eggs carry pathogenic bacteria, mold or parasite eggs. Some parents use boiled water to wash eggs with sugar for children to drink, due to the egg germs and parasite eggs can not be completely killed, easy to lead to diarrhea and parasitic diseases. If there is salmonella in the egg, it will also cause food poisoning. Recently found that the eggshell may be with 0-157 enterohemorrhagic E. coli, even if the amount of bacteria is very small, if the raw egg, but also enough to cause food poisoning. Folk people eat raw eggs to treat pediatric constipation, not only can not cure constipation, but also infected with toxoplasmosis of human and animal ****. The onset of this disease is more acute, almost all organs of the body by the invasion of toxoplasmosis caused by lesions, serious cases will also lead to death. Therefore, the eggs must be cooked to eat, to eat the best steamed eggs, should not use boiling water to wash eggs, not to eat raw eggs.