An RBC blood test identifies if the number of red blood cells you have is normal.

Measuring RBCs can help diagnose anaemia, a condition where the body doesn’t have enough healthy red blood cells. A low red blood cell count is a key indicator of anaemia, which can have many root causes.

RBC blood tests can also be used to help diagnose other conditions that affect red blood cells, such as kidney problems, a type of white blood cell cancer, or problems with the bone marrow.

Symptoms of a low red blood cell count may include:

• Feeling weak or tired more often than usual
• Headaches
• Problems concentrating or thinking
• Irritability
• Loss of appetite
• Numbness and tingling of hands and feet

With severely low red blood cell counts, symptoms may include:

• Blue colour to the whites of the eyes
• Brittle nails
• Desire to eat ice or other non-food things (pica syndrome)
• Light-headedness when you stand up
• Pale skin colour
• Shortness of breath with mild activity or even at rest
• Sore or inflamed tongue
• Mouth ulcers
• Abnormal or increased menstrual bleeding in females
• Loss of sexual desire in men

If your anaemia is mild or has developed slowly over a long period of time, you may not notice any symptoms.

Specific forms of anaemia may have different symptoms, depending on the cause.

An above-normal concentration of red blood cells is sometimes called polycythaemia, or erythrocytosis. This makes your blood thicker than it should be, causing the flow of blood to be sluggish, which can increase your risk for blood clots.

Many of the symptoms of a high red blood cell count are caused by the slower flow of blood, although sometimes people don’t experience any symptoms at all.

Symptoms of a high red blood cell count may include:

• Discomfort in the chest or abdomen
• Tiredness
• Headaches and dizziness
• Blurred vision
• Sleep disturbances
• Joint pain
• Abnormal skin sensations, such as tingling, tickling, pricking, itching, numbness or burning
• Nosebleeds
• Gout
• Tinnitus

Having an RBC blood test is very simple. You don’t need to prepare for the test but it’s recommended that you stay well hydrated with water before your test. This is because dehydration is a common cause of high blood cell counts.

The blood sample is taken from a vein in your arm, as opposed to using a finger-prick blood test, because results tend to be more accurate this way. The test is relatively painless, except for a slight pricking sensation as the phlebotomist inserts the needle. The blood sample is then sent to a laboratory for testing.

Our full body private health checks are designed for busy people who want to take control of their health. Our tests are quick, accurate, convenient and completely stress-free. No waiting for an appointment, no invasive procedures, no embarrassing questions, no long travel times and no busy waiting rooms.

Trained phlebotomists carry out all tests in our 350 venues across the UK and Ireland, so you get accurate professional health checks within 20 minutes of your home. Our private health checks include all the tests you need to take a proactive approach to monitoring and improving your health.

Any individual tests can be added to any full body health check. Just book one of our full body private health assessments and call us before your appointment to add an extra test.