Red blood cells transport oxygen throughout your body, including to vital organs and tissues. They also help your body get rid of carbon dioxide. Too little or too many red blood cells may be associated with a variety of health conditions.
Red blood cells (erythrocytes) are one of three main components in your blood, along with white blood cells and platelets. Produced by your bone marrow, red blood cells play a key role in transporting oxygen through your body.
Both a lack of red blood cells and too many of these cells can be linked to a variety of possible health problems. You might also experience noticeable symptoms of red-blood-cell-related conditions.
Learn more about these important blood cells, including their functions in the body, the health conditions related to abnormal red blood cell counts, and how a doctor might diagnose and treat them.
Red blood cells help deliver oxygen to tissues and organs, and also remove carbon dioxide from other body cells.
Red blood cells move oxygen from your lungs via your arteries. This includes delivering oxygen to vital organs and tissues. Red blood cells are able to accomplish this
However, the amount of oxygen delivered ultimately depends on how many hemoglobin-containing red blood cells you have. Another consideration is the quality of your red blood cells and their ability to function in your body overall.
While red blood cells are primarily known for oxygen delivery, they also collect carbon dioxide back into the lungs
Your bone marrow is responsible for producing red blood cells. In all, each red blood cell lives for an average of
Red blood cells look similar to disks. They don’t have nuclei, are circular and flat-shaped, and are concave on both sides. This makes it
Red blood cell counts can be higher or lower than normal, which can be related to numerous medical conditions. They tend to decrease with age.
Medical conditions that affect a low red blood cell count
A low red blood cell count is known as anemia. Common medical conditions associated with anemia include:
- Iron deficiency anemia: A low red blood cell count means your body will not get enough iron. This can be caused by heavy menstruation, blood loss, and gastrointestinal diseases. Iron deficiency anemia is treatable with dietary changes, iron supplements, or blood transfusions.
- Nutritional deficiencies: Certain nutrients, such as vitamins B6, B9 (folate), and B12 all help create healthy red blood cells. A doctor may recommend dietary changes or B-vitamin-specific supplements if lab tests reveal a deficiency of any of these micronutrients.
- Excessive blood loss: While not as common, excessive blood loss from an injury or internal bleeding can lead to a low red blood cell count. Both medical conditions are treatable with a red blood cell transfusion.
- Chronic kidney disease: Anemia is common in chronic kidney disease, and it’s caused by a lack of erythropoietin hormones. Produced by the kidneys, erythropoietin normally signals your body to make new red blood cells. Iron supplements or erythropoiesis-stimulating agent injections are typically prescribed to treat anemia that kidney disease causes.
- Certain cancers: Leukemia, a type of blood cancer, may crowd out red blood cells, reducing their numbers. Also, certain tumors may prevent healthy blood cell formation in the bone marrow. These conditions
may be treated with red blood cell transfusions. - Cancer treatments: Both chemotherapy and radiation therapy
may destroy red blood cells and cause anemia. In such cases, a doctor may recommend a red blood cell transfusion.
Medical conditions that affect a high red blood cell count
Also known as erythrocytosis, a high red blood cell count may be caused by:
- severe dehydration
- smoking
- congenital heart disease
- pulmonary fibrosis (scarring of your lungs)
- hypoxia (low blood oxygen)
Treatment or lifestyle changes can help with the above causes of a high red blood cell count.
However, if red blood cell levels remain high, a doctor may recommend other treatments to address the issue directly. Options include:
- hydroxycarbamide (Hydrea) tablets
- interferon injections
- venesection (blood removal) procedure
The exact symptoms of red blood cell-related health conditions can vary on the underlying cause. For example, anemia can cause the following signs and symptoms:
- pale skin
- weakness
- fatigue
- shortness of breath
- rapid heartbeat
- headaches
- dizziness
- depression
- brain fog
Possible signs and symptoms of erythrocytosis may include:
- itchy skin
- red or darkening skin, depending on skin tone
- blurry vision
- headaches
- dizziness
- fatigue
- confusion
- abdominal discomfort
- increased nosebleeds
- easy, or unexplained bruising
- high blood pressure
- gout
If a doctor suspects an issue with red blood cells, they will order tests to help diagnose and treat the underlying cause. Consider some of the following important information about red blood cell counts and ranges you can discuss with them beforehand.
A red blood cell range is considered typical between 4.6 and 6.2 million cells per microliter (cells/μL) for males and 4.2 to 5.4 million cells/μL for females.
Other tests may be needed to help diagnose anemia and other red blood cell-related conditions, such as providing hemoglobin measurements.
Normal red blood cell counts vary in children based on age and sex. A normal red blood cell count ranges between 4.5 and 5.3 million cells/μL for males ages 12 to 18 years, while the range is 4.1 to 5.1 million cells/μL for females of the same age group.
A doctor can determine your red blood cell count as part of a complete blood cell (CBC) test. This blood test also measures white blood cell and platelet counts. Collectively, a CBC test can determine whether your blood cells are within the normal range, including red blood cells.
The fastest way to increase red blood cells is through a transfusion. A red blood cell transfusion helps replenish red blood cells in your body, along with vital hemoglobin. Transfusions are used to treat severe anemia or to replenish losses related to internal bleeding.
Red blood cells are a critical component of your blood. These disc-shaped cells are produced by your bone marrow and then transported throughout the body to deliver essential oxygen. They also remove carbon dioxide waste, which is delivered to your lungs for removal.
Certain medical conditions, lifestyle habits, or nutritional deficiencies can cause either a depletion or influx of red blood cells. Treatment usually involves addressing the underlying issue, although sometimes transfusions or medications are needed.
A doctor can confirm red blood cell issues with blood tests. You may also consider speaking with a healthcare professional if you have possible symptoms that might point to a problem with red blood cells, such as weakness, fatigue, or dizziness.