Healthy red blood cells are round discs, each with a depression in the center, which are not clumped together. Normal levels vary with age, sex, and geographic location such as high altitude. The count is usually done electronically. An over abundance of red blood cells can indicate a condition known as polycythemia, and too few, anemia. Hematocrit measures the percent of packed red blood cells.
Normal values vary with sex, age and weight.
They are responsible for producing antibodies which look for and destroy specific foreign antigens. White blood cells have a much shorter life than red cells, and stress can shorten that life span to as little as 2-3 hours. An elevated WBC or white blood cell count can be an indicator of infection or of some forms of cancer. Identifying which white cells are elevated can be an indication of the problem, for example, allergy, infection or leukemia. Normal WBC is from 4,000 to 10,000 per microliter of blood.