Vitamin Deficiency
One of the worst types of anemia you can get would be the autoimmune condition known as pernicious anemia. This kind of anemia occurs when the body does not absorb or produce vitamin B12 in adequate amounts. Sometimes, pernicious anemia is caused by a diet that lacks folate and B vitamins.
Another reason one would develop pernicious anemia is as a secondary complication to a digestive condition, like Celiac disease or Crohn’s disease, since the body cannot absorb nutrients and vitamins from certain foods.
