Alkaline phosphatase is an enzyme involved in many chemical reactions in the body. Primarily concentrated in the liver and bones, alkaline phosphatase levels are generally evaluated as part of a liver function laboratory test. Elevated levels may indicate damage or disease of the liver, or bone diseases such as osteomalacia or Paget's disease. Although rare, low levels of alkaline phosphatase may occur and are generally due to genetic conditions or nutritional deficiencies.
Malnutrition
Malnutrition can cause low levels of alkaline phosphatase in the blood. Deficiencies in vitamin B6, folic acid and vitamin C can lead to alkaline phosphate deficiencies as well as an excessive intake of vitamin D. Hypophosphatasia, or low levels of phosphorous, zinc and protein deficiencies can also cause abnormally low levels, according to Dr. Jeremy Kaslow.
Hypophosphatasia
Hypophosphatasia is a rare genetic disorder affecting bone and teeth development that occurs in approximately 1 in every 100,000 births, according to Orphanet. Abnormal bone development is caused by a defect in bone mineralization -- a process where minerals are added to bone -- and low levels of alkaline phosphate in the blood and bone. The disorder weakens and softens bones, resulting in skeletal abnormalities, such as short limbs, as well as other sometimes serious health complications such as respiratory problems.
Other Causes
Several medical conditions may cause lower than normal levels of alkaline phosphatase. These include problems with the thyroid glands such as hypothyroidism or impaired parathyroid gland functioning. Pernicious anemia, or low red blood cell counts due to a decreased ability to absorb vitamin B-12, may also lower ALP levels, according to Dr. Jeremy Kaslow.
