Understanding the WBC (white blood cell) count
A white blood cell (WBC) count is a test that measures the number of white blood cells in your body. This test is often included with a complete blood count (CBC). The term “white blood cell count” is also used more generally to refer to the number of white blood cells in your body.
There are several types of white blood cells, and your blood usually contains a percentage of each type. Sometimes, however, your white blood cell count can fall or rise out of the healthy range.
WBCs, also called leukocytes, are an important part of the immune system. These cells help fight infections by attacking bacteria, viruses, and germs that invade the body.
White blood cells originate in the bone marrow but circulate throughout the bloodstream. There are five major types of white blood cells:
The symptoms of a low WBC count include:
High WBC counts don’t often cause symptoms, although the underlying conditions causing the high count may cause their own symptoms.
The symptoms of a low WBC count may prompt your doctor to recommend a WBC count. It’s also normal for doctors to order a CBC and check your WBC count during an annual physical examination.
A healthcare provider or lab technician needs to draw blood to check your WBC count. This blood sample is taken either from a vein in your arm or a vein on the back of your hand. It only takes a couple of minutes to draw your blood, and you may experience minor discomfort.
The healthcare provider first cleans the needle site to kill any germs and then ties an elastic band around the upper section of your arm. This elastic band helps the blood fill your vein, making it easier for the blood to be drawn.
The healthcare provider slowly inserts a needle into your arm or hand and collects the blood in an attached tube. The provider then removes the elastic band from around your arm and slowly removes the needle. Finally, the technician applies gauze to the needle site to stop the bleeding.
Healthcare providers use a different technique when drawing blood from young children and infants: Providers first puncture the skin with a lancet (a pricking needle), and then use a test strip or a small vial to collect the blood.
Results are sent to a lab for review.
Having your blood drawn is a simple procedure, and complications are extremely rare.
It can be difficult to take blood from people with small veins. The lab technician may be unable to locate a vein, or once the needle is inside the arm or hand, they may have to move the needle around in order to draw blood. This can cause a sharp pain or a stinging sensation.
Rare complications include:
A WBC count requires no specific preparation. You simply schedule an appointment with your doctor or set up an appointment at a local medical laboratory.
Certain medications can interfere with your lab results and either lower or increase your WBC count. The drugs that may affect your test results include:
Prior to having your blood drawn, tell your doctor about all prescription and nonprescription medications that you’re currently taking.
Abnormal test results are classified by numbers that are higher or lower than the normal range for your age.
A low or high WBC count can point to a blood disorder or other medical condition. To identify the exact cause of a high or low WBC count, your doctor will take several factors into consideration, such as your list of current medications, symptoms, and medical history.
Leukopenia is the medical term used to describe a low WBC count. A low number can be triggered by:
Leukocytosis is the medical term used to describe a high WBC count. This can be triggered by:
After diagnosing the cause of a high or low WBC count and recommending a treatment plan, your doctor will periodically recheck your WBCs.
If your WBC count remains high or low, this can indicate that your condition has worsened. Your doctor may adjust your treatment.
If your WBC count shows a normal range, this usually indicates that the treatment is working.
Are there any foods I can eat that will help increase my WBC count?
No specific foods or diet is proven through research to increase the production of white blood cells.
It’s important to include a good source of protein in your diet, as amino acids found in protein are needed to build WBCs.
Vitamins B-12 and folate are also needed to produce WBCs, so consider adding a multivitamin and mineral supplement daily. Though not proven, some believe that adding vitamin C, vitamin E, zinc, garlic, selenium, and even spicy foods to your diet can boost the immune system.
If you’re being treated for cancer or other causes of leukocytosis, talk to your doctor before taking any supplements, as they might interfere with treatments.
Deborah Weatherspoon, PhD, RN, CRNAAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.