<Tr> <Th> Frequency </Th> <Td> 1 per 1000 people </Td> </Tr> <Tr> <Td_colspan="2"> (edit on Wikidata) </Td> </Tr> <P> Vitamin B deficiency anemia, of which pernicious anemia is a type, is a disease in which not enough red blood cells are present due to a lack of vitamin B . The most common initial symptom is feeling tired . Other symptoms may include shortness of breath, pale skin, chest pain, numbness in the hands and feet, poor balance, a smooth red tongue, poor reflexes, depression and confusion . Without treatment some of these problems may become permanent . </P> <P> Although pernicious anemia technically refers to cases resulting from not enough intrinsic factor, it is often used to describe all cases of anemia due to not enough vitamin B. Lack of intrinsic factor is most commonly due to an autoimmune attack on the cells that create it in the stomach . It can also occur following the surgical removal of part of the stomach or from an inherited disorder . Other causes of low vitamin B include not enough dietary intake (such as in a vegan diet), celiac disease, or tapeworm infection . When suspected, diagnosis is made by blood and, occasionally, bone marrow tests . Blood tests may show fewer but larger red blood cells, low numbers of young red blood cells, low levels of vitamin B, and antibodies to intrinsic factor . </P>

A deficiency of this substance leads to pernicious anemia
find me the text answering this question