There may be some truth to that.
Anemia is a shortage of hemoglobin in red blood cells.
Hemoglobin is the substance that carries oxygen from the lungs to the body's cells. Because oxygen is necessary to keep cells going, a shortage in hemoglobin causing a shortage in oxygen reaching cells can lead to tiredness or listlessness. Other symptoms of anemia include shortage of breath, heart palpitations and dizziness when standing suddenly or for long periods of time. Anemia is often caused by a lack of iron in the diet or by bleeding, such as from a bleeding ulcer. Doctors at UT Southwestern Medical Center say it's important to find the cause of anemia because it often can be a symptom of another health problem.