Functions in metabolic regulation The imidazole of histidine can form coordination compounds with Fe2+or other ions, promoting the iron absorption. So histidine can be used in prevention of anemia. Histidine can reduce gastric acidity, ease the pain from gastrointestinal surgery, alleviate vomiting during pregnancy and burning sensation of the stomach, autonomic nervous inhibit the gastrointestinal ulcers caused by autonomic nervousness, and also be effective to allergic diseases such as asthma. In addition, due to its effect of dilating blood vessels and lowering blood pressure, histidine can be used for treatment of diseases such as angina and heart failure. The histidine content in the blood of patients with rheumatoid arthritis reduced significantly, but after the treatment of histidine, it is found that indicators including its grip strength, walking and erythrocyte sedimentation rate were improved.Adults can synthesize histamine, but children under 10 can not, so the requirement of histidine among children aged below 10 should be metby food supply.