Anemia is the most common blood disorder, and according to the National Heart, Lung, and Blood Institute, it affects more than 3 million Americans and an estimated 1.62 billion people in the world. Anemia is diagnosed as any condition in which our body does not produce enough healthy red blood cells. The condition has been discovered to date back to more than 4,000 years ago and is the most common blood disorder. Anemia is not strictly a disease, but a disorder. It is often a byproduct of other diseases that disrupt the body's ability to produce healthy red blood cells.Unfortunately, there is no one specific cause of anemia. Due to the sheer number of anemia types, it can sometimes be difficult to pinpoint the exact cause.A patient's diet can be a cause of anemia. A lack of iron or vitamin-rich foods severely impacts the body's capacity to produce enough healthy red blood cells.The most common symptom of anemia, regardless of type, is a feeling of fatigue and a lack of energy.Women who are menstruating or pregnant and people with chronic medical conditions are most at risk for this disease.