Final answer:
An abnormally low hemoglobin measurement indicates anemia, a condition with various causes such as blood loss or decreased RBC production. Sickle cell anemia and thalassemia are types of anemia that affect the blood's ability to deliver oxygen.
Step-by-step explanation:
An abnormally low hemoglobin measurement is an indication of anemia, which is either a reduced number of red blood cells (RBCs) or a reduced amount of hemoglobin in each red blood cell. Anemia can be a result of different conditions, including blood loss, faulty or decreased RBC production, and excessive destruction of RBCs. Diseases like sickle cell anemia and thalassemia decrease blood's ability to carry oxygen due to the abnormal shape of red blood cells or the absence of necessary hemoglobin subunits, respectively.
Anemia affects more than 3.5 million Americans, making it a significant health condition. Symptoms often include fatigue, lethargy, and an increased risk for infection, as anemia leads to reduced oxygen delivery to body tissues. Diagnosing anemia may involve looking at the size of RBCs, their production rate and lifespan, or hemoglobin levels.