Red Blood Cell Count

Red blood cell (RBC) count measures the number of red blood cells in a given volume of blood. Red blood cells are vital because they carry oxygen from the lungs to the body's tissues and help remove carbon dioxide. A normal RBC count indicates the blood can efficiently deliver oxygen, supporting overall health. An abnormal count may suggest anemia (low count), which can cause fatigue and weakness, or polycythemia (high count), which can increase blood thickening and risk of clotting. Doctors use this test alongside other blood components to assess and diagnose various health conditions.