It is right that it is better to remove the head of the shrimp when eating crayfish. Because the head of the crayfish has a lot of internal organs, such as the stomach, heart, intestines, reproductive system, etc., contains a lot of bacteria and metabolites, easy to have diarrhea after eating. Crayfish head there are some heavy metal deposits, if the amount of food is relatively large, easy to arsenic poisoning; crayfish head also contains some parasites, if the cooking time is not enough, may cause parasitic infection. In addition, many people like to eat shrimp head “yellow”, but it is not shrimp eggs, but the crayfish hepatopancreas, that is, the liver and pancreas, easy to be contaminated by the aquatic environment enriched with heavy metals, but also easy to become a host for Schistosoma haematobium, Schistosoma hepatica and other parasites. If a large number of contaminated shrimp yolk consumption, may lead to excessive heavy metal content in the body; infection with parasites may appear cough, fever, nausea, epigastric fullness, hidden pain, diarrhea and other symptoms. In addition, when eating crayfish, try to avoid and some foods containing high tannins, especially some fruits, such as persimmons, containing tannins and crayfish head of some of the ingredients will react, resulting in diarrhea, nausea, vomiting. If there are allergic people try to eat less crayfish, to avoid allergic reactions, and gout people avoid eating or do not eat and drink beer together, so as not to trigger or aggravate gout. In short, the head of the shrimp is the place where the most toxins are absorbed and processed, and it is also the part that is most likely to accumulate pathogenic bacteria and parasites. Therefore, from a hygiene and health point of view, it is really not recommended to eat the head of shrimp.