The cells formed in bone marrow are enlarged, with a reduced capacity to carry oxygen. Your body needs vitamin B-12 and folic acid, a B vitamin, for red blood cells to mature normally. B-12, it's called pernicious anemia. This is an uncommon anemia that develops when red blood cells are destroyed faster than bone marrow can replace them. The result is a shortage of red blood cells to transport oxygen.
Early destruction can result from genetic defects or acquired defects.
Genetic defects in the red blood cell's physical or chemical makeup can lead to a rigid or elongated shape. The deformity causes red blood cells to become trapped in your spleen, where most are destroyed before the end of their normal lifespan. Sickle cells lodge in small arteries, causing acute pain and blood clots. Sickle cell anemia most often affects blacks of African-American descent and Hispanic Americans. Some artificial heart valves also increase the risk of red blood cell destruction by directly injuring cells.