Anemia is a low level of healthy red blood cells (RBC). RBCs carry oxygen from the lungs to the rest of the body. When red blood cells are low the body does not get enough oxygen. This can cause symptoms such as fatigue, pale skin, or irregular heartbeat.

Pernicious anemia is associated with problems absorbing vitamin B12. This vitamin is needed to make healthy RBCs. Over time the low vitamin B12 levels will reduce the number of new RBCs. The sooner pernicious anemia is treated, the better the outcome. If you suspect you have this condition, contact your doctor.

Red Blood Cells
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There are many possible causes of pernicious anemia. Some are listed below.

  • Atrophic gastritis (inflammation of the stomach)
  • Removal of all or part of the stomach
  • Immune system reaction to:
    • Intrinsic factor—a protein necessary for vitamin B12 absorption
    • Cells that produce both intrinsic factor and hydrochloric acid in the stomach
  • Genetics