Crab is a high-protein food with high nutritional value, but whatever food you eat needs to be in moderation, too much can be harmful to your body. In Western medicine, eating too much crab may trigger gout, cause allergic reactions, and even induce or aggravate cardiovascular disease, while in Chinese medicine, crab is cold and eating too much of it may damage the spleen and stomach, etc. I. Western medicine: 1, trigger gout: crab with high purine content, consuming too much crab may cause symptoms of gout, hyperuricemia, gout patients may aggravate the condition; 2, lead to allergic reactions: some people are allergic to crab, allergic people should eat less or even do not eat crab, otherwise it may cause diarrhea, vomiting, breathing difficulties and other allergic reactions; 3, induce or aggravate cardiovascular disease. The crab yolk and crab paste in crabs contain more cholesterol. Hypertension, hyperlipidemia and diabetic patients who consume too much crab will aggravate the disorder of lipid metabolism, which in turn will aggravate the symptomatic response to the disease, and too much for the general population will increase the risk of cardiovascular disease. In Chinese medicine, crab, like other foods, can easily damage the spleen and stomach, increase the burden on the gastrointestinal tract, and cause diarrhea and other symptoms. In addition, crab is cold, so women who are menstruating should eat less or even not eat crab to avoid causing discomfort from coldness in the uterus, severe dysmenorrhea, and reduced menstrual flow.