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Red Cell Count


Red Blood Cell (RBC) Count analyses the number of red blood cells in the blood. Red blood cells carry oxygen from the lungs to the rest of the body, where it can be used to fuel energy processes such as movement and respiration. They also carry carbon dioxide produced from cells back to the lungs so that it can be exhaled.

What might a low result mean?

A low RBC count can indicate that you have anaemia, meaning you have fewer RBCs than normal. Fewer red blood cells mean you have less capacity to transport oxygen around the body, resulting in less 'fuel' for essential energy processes. This is the major cause of fatigue that people with anaemia typically experience.

Anaemia has a wide variety of causes, including nutritional deficiencies such as lack of iron or folic acid, over-hydration as well as bleeding and bone marrow disorders.

What might a high result mean?

An elevated RBC count can indicate that you have polycythaemia, meaning that you have a greater number of RBCs than normal. This often arises as the body increases red blood cell production in order to compensate for chronically low oxygen levels caused by lung disease, or living at altitude.

Raised RBC counts can also be caused by dehydration, smoking, and kidney tumours which stimulate excess RBC production.