<unk>  is the deficiency of folic acid, which is a necessary compound for the normal production of red blood cells. Folic acid is part of the vitamin B complex, also called vitamin B9 or pteroylglutamic acid. The recommended daily amount of<unk>  for adults is 400 micrograms (mcg). Adult women who are planning pregnancy or could become pregnant should be advised to get 400 to 800 mcg of folic acid a day. The deficiency of folic acid is associated with a type of anemia, characterized by enlarged blood corpuscles, called megaloblastic anemia.The anemia is thought to be due to problems in the synthesis of DNA precursors, specifically in the synthesis of thymine, which is required for normal erythropoesis and dependent on products of the MTR reaction. Other cell lines such as white blood cells and platelets are also found to be low due to impaired division of the precursor cells.  Bone marrow examination may show megaloblastic hemopoiesis. The anemia is easy to cure with folic acid supplementation.
Folate deficiency
Zinc deficiency
Familial isolated vitamin E deficiency
Biotin deficiency
Manganese deficiency 
Vitamin B12 deficiency
Vitamin A deficiency
Copper deficiency