If you are reading this, chances are you don’t know what hematocrit is yet (or even how to pronounce it). You’re not alone. Hematocrit [huh-ma-tuh-krit] is the amount of red blood cells in your blood. Hematocrit test results, or hematocrit levels, are given as a percentage of the total volume of your blood. This is related to hemoglobin, which is measured every time you donate blood.

Your hematocrit level is important because having too many or too few red blood cells can cause health problems. You also need to have the right amount of hemoglobin within your red blood cells. Hemoglobin delivers oxygen to your organs and tissues and carries carbon dioxide back to the lungs to be expelled. 

A hemoglobin test measures the amount of hemoglobin in your blood. Normal hemoglobin range for adult males is 13.5 to 17.5 grams per deciliter (g/dL); for adult females it is 12.0 to 15.5 g/dL. 

Females need at least 12.5 g/dL to safely donate blood, males need 13.0 g/dL. For the automated donation known as Power Red, where two units of red cells are donated as opposed to one, hemoglobin levels need to be higher.    
 

Normal hematocrit levels

Your age, gender and ethnicity can affect hematocrit levels, but generally a healthy range for adult males is between 38% and 50% and for adult females it is 36% to 45%. Hematocrit levels are approximately three times the hemoglobin level, as they are related by the amount of hemoglobin in normal red blood cells.

Symptoms of a low hematocrit (or hemoglobin) level can indicate anemia and may include tiredness, dizziness or lightheadedness, shortness of breath, pale skin and headaches. High levels, or too many red blood cells, could mean you have polycythemia or erythrocytosis. Nosebleeds, headaches and shortness of breath can be signs of erythrocytosis. Common symptoms of polycythemia include excessive sweating, dizziness, headaches and itchy skin.

If you experience symptoms of low or high hematocrit or hemoglobin levels, see your health care provider.

Testing for hemoglobin levels

Vitalant does not test for hematocrit, but every time you donate blood we test for hemoglobin, which provides similar information. While hematocrit and hemoglobin measurements have slightly different normal ranges, both determine if your body has a healthy amount of red blood cells.

If you receive an abnormally high or low result on your hemoglobin test, you should consult with your health care provider.

Donating blood can help monitor your health

Every time you donate blood, you receive a mini-physical where not only is your hemoglobin checked, but also your blood pressure, pulse and cholesterol levels. You will also find out your blood type. 

Test results are posted in your private online donor account, so you can keep track of this information and share it with your health care provider.