The normal range for LDH in the human body is 140 units per liter to 280 units per liter, as stated by WebMD. LDH, or lactic acid dehydrogenase, is an enzyme that the human body utilizes in order to produce energy.
LDH is present in virtually every tissue in the human body, according to WebMD. This enzyme raises in concentration whenever cells or tissues become damaged in order to help repair the cells. For this reason, LDH levels in the body can be measured in order to help diagnose a variety of illnesses include lung disease, anemia and liver disease.