Blood health
Red blood cell count (RBC)
RBC, erythrocyte count
Included in every MyHealthspan membership: Focus, Baseline, and Complete.
Compare membershipsCounting the cells that move oxygen.
Your red blood cell count is the number of red cells in a set volume of blood. These cells carry oxygen from your lungs to every tissue, so the count helps assess anemia and conditions where the body makes too many red cells.
The count makes the most sense next to its partners.
Red cell count, hemoglobin, and hematocrit usually rise and fall together. Reading all three, plus the average red cell size (MCV), gives a fuller picture than any one result alone.
For example, thalassemia trait (an inherited difference in how hemoglobin is made) can produce many small red cells. The count may then look normal or even high while each cell carries less hemoglobin.
Count, size, and hemoglobin content work best when read together.
Questions
What can raise or lower my red cell count?
Dehydration, smoking, high altitude, sleep apnea, and anabolic steroid use can raise it. Pregnancy, blood loss, low iron or B vitamins, kidney disease, and heavy alcohol use can lower it. A clinician reads your result with your history to sort out which applies.
What happens if my result is out of range?
Every blood test result is reviewed by a licensed nurse practitioner. A result slightly outside the range is read alongside your hemoglobin, hematocrit, and MCV, and it's often rechecked before anyone draws conclusions.