Anemia is a medical condition in which a person has a lower than normal number of red blood cells in the blood, usually measured by a decrease in the amount of hemoglobin. Hemoglobin is the red pigment in red blood cells that transports oxygen.
Potential causes include blood loss, nutritional deficits, many diseases, medication reactions, and various problems with the bone marrow. Severe anemia can cause low oxygen levels in vital organs such as the heart and can lead to heart attack.
