what is hemoglobin a measure of
Definition. A hemoglobin test measures the amount of hemoglobin in your blood. Hemoglobin is a protein in your red blood cells that carries oxygen to your body's organs and tissues and transports carbon dioxide from your organs and tissues back to your lungs.If a hemoglobin test reveals that your hemoglobin level is lower than normal, it means you have a low red blood cell count (anemia).Anemia can have many different causes, including vitamin deficiencies, bleeding and chronic diseases.f a hemoglobin test reveals that your hemoglobin level is lower than normal, it means you have a low red blood cell count (anemia).