What is the cause of high alkaline phosphatase? Alkaline phosphatase is an enzyme that is widely distributed in the liver, bones, liver, kidneys, placenta and other tissues of the body via the liver gland and excreted outside the liver. This enzyme has many isoenzymes, so it is distributed in the liver, bone cells, placenta, tumor cells, and the epithelium of the small intestine or fibroblasts, so elevated alkaline phosphatase is mostly seen in physiological increases, such as some children in the physiological bone development period, alkaline phosphatase will be 1-2 times higher than normal, and some children who grow faster may be higher. Adolescents in the growth phase can also cause an increase in alkaline phosphatase, bones grow faster, pregnant women and eating foods with high fat content can also cause an increase in alkaline phosphatase. There are also pathological elevations, mostly in orthopedic diseases, such as rickets, chondromalacia, primary malignant tumors of the bones or metastatic bone tumors in the bones, which can lead to elevated alkaline phosphatase. Hepatobiliary disorders of the liver, such as anal duct intestinal blockage, extrahepatic bile duct stones, hepatic duct sclerosis, hepatocellular carcinoma, and capillary biliary hepatitis, can cause an increase in alkaline phosphatase of hepatobiliary origin. Hyperparathyroidism and other causes can also cause an increase in alkaline phosphatase.