Blood contains three vital types of cells; red blood cells that contain the iron-rich protein hemoglobin to carry oxygen, white blood cells that protect the body from foreign invaders, and platelets that help blood to clot. A condition of low iron, known as anemia, can cause a low number of red blood cells, or occur due to a low number of red blood cells. Because bone marrow produces new blood cells, conditions and diseases that affect the ability of the bone marrow to function can lead to a low white cell count and a low number of red blood cells, which results in a low iron level.
Aplastic Anemia
Aplastic anemia describes a blood disorder in which the stem cells---the undifferentiated cells in the bone marrow--become damaged and unable to produce new blood cells. Because red blood cells live only 120 days and white blood cells less than one day, these bone marrow cells must continually produce new blood cells, according to the National Heart Lung and Blood Institute.
Aplastic anemia can occur due to acquired conditions such as infectious diseases or autoimmune disorders or due to inherited conditions such as Shwachman-Diamond syndrome or dyskeratosis congenital. Damage to the stem cells prevents the bone marrow from producing new blood cells resulting in a low level of white blood cells and red blood cells.
Leukemia
The stem cells in the bone marrow can make abnormal white blood cells resulting in a specific type of cancer know as leukemia. These leukemic cells do not die when they should; therefore they crowd out normal white blood cells and red blood cells causing a deficiency in both, as described by the National Cancer Institute. This lack of functioning white blood cells causes frequent infections and a lack of red blood cells causes feelings of weakness and tiredness---both characteristic of low iron levels.
Chemotherapy
Chemotherapy describes a type of medical treatment often used to treat diseases such as cancer. Chemotherapy utilizes drugs to target and kill rapidly dividing cells. Because patients take most chemotherapy drugs either orally or intravenously, the drugs travel throughout the bloodstream. This exposes healthy cells to the detrimental effects of the drugs.
To keep up with the production of new blood cells, the stem cells in the bone marrow divide and grow rapidly. Chemotherapy destroys stem cells leading to one of the main side effects of low blood counts, according to Chemocare.com. A low red blood cell count decreases the level of iron circulating in the body, therefore decreasing the amount of oxygen available to cells. This results in symptoms of fatigue, weakness and shortness of breath. A low white blood cell count leaves patients vulnerable to serious and even life-threatening diseases.
