Maintaining a normal level of healthy white blood cells can help reduce the risk of infection and is a key component of overall health. If you have a low WBC count, called leukopenia, you may be at an increased risk of developing infections.
Importantly, you don’t want extremely high levels of white blood cells. Increased WBC levels—known as leukocytosis—are a sign the body is responding to a stressor. Stressors that increase WBC levels can be physical, such as an infection, cancer, or an autoimmune disorder, or emotional.
This article discusses the function of white blood cells, the causes of increased and decreased white blood cell counts, and the medications and habits needed to maintain a healthy white blood cell count.
Types of WBCs and Their Functions
Several types of white blood cells are found in your body, and each has specialized functions. The major WBC types are:
Neutrophils: These cells make up the majority of the white blood cell population. Neutrophils are the primary cells responsible for responding to bacterial infections. Lymphocytes: Lymphocytes are the second most common white blood cell subtype. The lymphocytes include T cells and B cells, which help support the immune system’s response to infections, cancers, and other stresses. Eosinophils: These white blood cells are primarily responsible for allergies and responding to parasitic infections. Monocytes: These WBCs are the first to respond to an infection. These blood cells include macrophages and dendritic cells and can be elevated in autoimmune disorders and chronic infections.
WBCs fight infection and are also an integral part of the body’s ability to fend off cancer. Since cancer cells are foreign to the body, white blood cells such as lymphocytes can help eliminate cancer cells.
Some cancers can evade detection by the immune system, but medical advances have created new therapies and treatments that use white blood cells to detect and target cancer, such as checkpoint inhibitors and cell therapies.
How White Blood Cells Are Measured
The most common test to detect WBC levels is called a complete blood count, or CBC.
The CBC can provide information on the total number of white blood cells in the body, as well as the specific types of white blood cells. The CBC is a useful diagnostic tool because it can provide healthcare providers with information on your white blood cell count and the potential causes of an elevated white blood cell count.
Another test that is used for white blood cell assessment is called flow cytometry. This is a more advanced test that is typically used for evaluating cancerous white blood cell counts. Cytometry analyzes each cell individually and can precisely determine subtypes of white blood cells.
Causes of Increased White Blood Cell Counts
There are many causes of elevated WBC counts. WBC levels can rise due to the following:
InfectionMedications, particularly steroid medicationsPregnancy Surgery or injuryAllergic reactionAutoimmune disordersStress, both emotional and physicalBone marrow disorderCancer, particularly leukemia and lymphoma Smoking
Causes of Low WBC Counts
While many conditions can lead to high white blood cell counts, there are only a few major causes of low white blood cell counts. These include:
Chemotherapy medicationsImmunosuppressive medicinesMedicationsBone marrow failureAutoimmune disorders
If you have a low white blood cell count, you should ask your healthcare provider to determine the cause and the best course of treatment. In some cases, a very low white blood cell count can increase your risk of developing serious infections.
Medicines That Increase WBC Count
If you have a low white blood cell count, your healthcare provider may prescribe medications to stimulate white blood cell production. These medications, such as Neupogen (filgrastim), Neulasta (pegfilgrastim), and others, are all part of a family of drugs called granulocyte colony stimulators (G-CSF). These medications work by jump-starting the bone marrow to produce more white blood cells.
Foods That Increase WBC Counts
If your white blood cell level is low, there are changes you can make to try to increase it. Always consult with a healthcare professional before starting any new treatments, including diets, that may disrupt your WBC count. Very low WBCs are medical emergencies that require prompt treatment.
A healthy diet, rich in vegetables, and protein is a good way to maintain a healthy immune system.
A Mediterranean diet, which consists of whole grains; fruits and vegetables; beans, nuts, and seeds; healthy fats; moderate amounts of fish and poultry; and limited amounts of red meat, has been shown to help boost white blood cell levels. Foods such as blueberries, strawberries, and leafy green vegetables can help reduce the risk of developing certain immune disorders. These whole foods are a good source of antioxidants, which can help support the function of a healthy immune system.
As much as possible, look to get your nutrients and antioxidants from foods. You should consult with a healthcare professional before starting any supplements.
Summary
Maintaining a healthy white blood cell count can help reduce the risk of infection and is a key component of overall health. If you have a low WBC count you may have leukopenia, which increases your risk of developing infections.
A Word From Verywell
If you have a low white blood cell count, there are several strategies you can use to boost your white blood cell levels. Work with your healthcare provider to see if changes in your medications or your diet can help increase your levels.
