A complete blood count (CBC) test is a routine blood test that measures the number and quality of different types of blood cells in your body. It can be used to evaluate your overall health and detect a wide range of disorders, including anemia, infection, and leukemia.
Here are some key points about a CBC test:

The test measures the following components of your blood:
- Red blood cells (RBCs): These cells carry oxygen to your body’s tissues. A low RBC count may indicate anemia.
- White blood cells (WBCs): These cells help fight infection and other diseases. A high WBC count may indicate an infection or inflammation.
- Platelets: These cells help your blood clot. A low platelet count can lead to bleeding and bruising.
The test may also measure the following values:
- Hemoglobin: This is a protein in RBCs that carries oxygen. A low hemoglobin level may indicate anemia.
- Hematocrit: This is the percentage of RBCs in your blood. A low hematocrit level may also indicate anemia.
- Mean corpuscular volume (MCV): This is the average size of your RBCs. A larger-than-normal MCV may indicate a deficiency in certain vitamins, such as folic acid or vitamin B12.
A CBC test is usually performed as part of a routine health checkup or to help diagnose and monitor a medical condition.
The test requires a small blood sample, which is typically drawn from a vein in your arm.
The results of the test are usually available within a few days. Your healthcare provider will interpret the results and discuss them with you.
A CBC test is generally safe and carries little risk. However, there may be slight discomfort or bruising at the site where the blood is drawn.
It’s important to follow your healthcare provider’s instructions and to let them know if you have any concerns about the test.
What diseases can a CBC detect?
- Anemia: A CBC test can detect low levels of red blood cells, hemoglobin, or hematocrit, which may indicate anemia. Anemia is a condition in which your body doesn’t have enough red blood cells to carry oxygen to your body’s tissues. It can be caused by a variety of factors, including blood loss, poor nutrition, and certain medical conditions.
- Infection: A CBC test can detect an increase in white blood cells, which may indicate an infection. White blood cells help fight infection and other diseases.
- Leukemia: A CBC test can detect abnormal levels of white blood cells, which may indicate leukemia. Leukemia is a type of cancer that affects the blood and bone marrow.
- Inflammation: A CBC test can detect an increase in white blood cells, which may indicate inflammation. Inflammation is the body’s response to injury or infection.
- Bleeding disorders: A CBC test can detect low levels of platelets, which may indicate a bleeding disorder. Platelets help your blood clot.
- Nutrient deficiencies: A CBC test can detect low levels of red blood cells, which may indicate a deficiency in certain nutrients, such as iron or folic acid. It can also detect larger-than-normal red blood cells, which may indicate a deficiency in certain vitamins, such as vitamin B12 or folic acid.
- Other medical conditions: A CBC test can also be used to help diagnose and monitor other medical conditions, such as cancer, kidney disease, and autoimmune disorders.
It’s important to note that a CBC test can detect the presence of certain disorders, but it can’t confirm a diagnosis. Additional testing may be needed to determine the cause of abnormal results.
What is CBC’s normal range?
A (complete blood count) CBC test measures the number and quality of different types of blood cells in your body. The normal range for each component of a CBC test may vary slightly depending on the laboratory that performs the test and the specific techniques and equipment used.
Here are the normal ranges for some common components of a CBC test:
- Red blood cells (RBCs): The normal range for RBCs is typically between 4.7 million and 6.1 million cells per microliter (cells/mcL) for men and between 4.2 million and 5.4 million cells/mcL for women.
- White blood cells (WBCs): The normal range for WBCs is typically between 3,500 and 10,500 cells/mcL.
- Platelets: The normal range for platelets is typically between 150,000 and 450,000 cells/mcL.
- Hemoglobin: The normal range for hemoglobin is typically between 13.5 and 17.5 grams per deciliter (g/dL) for men and 12.0 and 15.5 g/dL for women.
- Hematocrit: The normal range for hematocrit is typically between 38% and 47% for men and 35% and 45% for women.
- Mean corpuscular volume (MCV): The normal range for MCV is typically between 80 and 100 femtoliters (fL).
It’s important to note that these values are just a general guide and may not apply to everyone. Your healthcare provider will interpret your test results based on your age, gender, and other factors. If any of your test results are outside the normal range, your healthcare provider will discuss them with you and may recommend additional testing or treatment.
What happens if CBC is abnormal?
There are many possible causes of an abnormal CBC, and the specific implications of an abnormal result will depend on the individual circumstances. Some possible causes of an abnormal CBC include:
- Anemia: This is a condition in which there are not enough red blood cells, which can lead to symptoms such as fatigue, shortness of breath, and pale skin.
- Infection: An increase in white blood cells can be a sign of infection.
- Bleeding disorders: A decrease in platelets can indicate a bleeding disorder, such as thrombocytopenia.
- Cancer: An abnormal CBC may be a sign of cancer, especially if there are abnormal white blood cells or low red blood cell counts.
If you have an abnormal CBC, it is important to speak with your healthcare provider to determine the cause and appropriate treatment. They may recommend further testing or treatment depending on the specific abnormalities found in your CBC.
How can I improve my CBC results?
There are several things you can do to improve your CBC results:
- Eat a healthy diet: A healthy diet that is rich in iron, folic acid, and other nutrients can help improve your red blood cell counts and overall CBC results. Good sources of iron include red meat, poultry, seafood, beans, and leafy green vegetables. Folic acid can be found in leafy green vegetables, nuts, beans, and fortified cereals.
- Exercise regularly: Regular physical activity can help improve your CBC results by increasing your red blood cell production and reducing your risk of anemia.
- Get enough rest: Getting enough sleep and rest can help your body produce the cells it needs to maintain a healthy CBC.
- Avoid smoking: Smoking can damage your blood cells and lead to an abnormal CBC. If you smoke, consider quitting to improve your overall health and CBC results.
- Avoid excessive alcohol consumption: Excessive alcohol consumption can lead to anemia and other problems with your blood cells. It is important to drink alcohol in moderation, if at all.
- Take supplements: If you are low in certain nutrients, your healthcare provider may recommend taking supplements to help improve your CBC results.
It is important to note that improving your CBC results may take time and may require a combination of lifestyle changes and medical treatment. It is always a good idea to speak with your healthcare provider for specific recommendations and guidance.