A normal white blood cell count is any number between 4,500 and 10,000 white blood cells per microliter of blood. Normal values may be different in different laboratories throughout the United States.
White blood cells are immune cells that are found in the bloodstream. In total, there are five main types of white blood cells: basophils, eosinophils, lymphocytes, monocytes and neutrophils. All these cells help the body fight infection. A white blood count that is too high or too low may indicate that there is a medical issue. Too few white blood cells is known as leukopenia and can lead to many infections. Too many white blood cells may be indicative of cancer.
Cigarette smoking, leukemia, severe stress, infection and tissue damage sometimes cause a high white blood cell count. Taking certain medications can also influence the white blood cell count.