Glossary
Erythropoietin: The hormone that regulates red blood cell production.

Erythropoiesis-stimulating agents (ESAs): A man-made drug which stimulates red blood cell production by mimicking the body's natural erythropoietin.

Fecal occult blood test: An analysis of a stool sample which can detect even the smallest traces of blood.

Inflammation: Your body's response to injury or irritation; often associated with pain, redness, heat, and/or swelling.

Iron deficiency: A shortage or low level of iron in the body, which can lead to anemia.

Causes for Deferral

Other Invisible Causes

Donating blood is a great way to help your community, but sometimes you can be turned down from donating because your blood count is too low. This is called being "deferred" and about 10% of people who attempt to donate are deferred because of a low blood count.1 Don't feel bad if you were deferred for this reason because it is one of the most common reasons people are not allowed to donate blood.2 After testing a sample of your blood, you may have been told your "iron is low", you have a "low blood count", "low hemoglobin" or "low hematocrit". Essentially, each of these terms means you do not have enough red blood cells in your body to donate blood.

The medical term for a lower than normal blood count is anemia and there are many reasons why it can develop. Two main causes involve Iron and Vitamin Deficiencies and Chronic Illnesses. A third type of cause may be an unknown illness, often affecting the digestive tract. Even though you were not allowed to donate on a particular day due to a low blood count, there are steps you can take to treat anemia and raise your blood count. Then you can return and try to donate again.

What conditions can cause a low blood count besides iron or vitamin deficiencies or chronic illnesses?

Conditions affecting the digestive tract can often cause bleeding, which results in lower blood counts and can lead to anemia. Some conditions which can cause this type of bleeding include stomach ulcers, growths in the intestine (polyps), colon cancer, and other less common diseases of the digestive tract. Certain medications can also cause bleeding of the digestive tract.18 If you notice blood in your stool, be sure to make an appointment with your doctor without delay.

Invisible Causes of Anemia

  • Stomach ulcers
  • Growths in intestines (polyps)
  • Colon cancer
  • Certain medications
  • Other diseases of the digestive tract

It can be difficult to tell if you are bleeding from your digestive tract because blood may not be visible in your stool. Even small, invisible amounts of blood lost through the digestive tract can lead to lower blood counts. If you were told you have a low blood count and you do not have a diagnosed chronic illness or an iron or vitamin deficiency, be sure to consult your doctor without delay.

Sometimes doctors may not be able to determine a cause of anemia. This is called unexplained anemia and it occurs in about one-third of all anemia cases in the elderly.26-28 There may be many reasons why a specific cause is not found, but some doctors believe it is due to mild or unrecognized chronic conditions. If your doctor cannot find a cause for your anemia, he or she will discuss with you the best way to manage your anemia and its symptoms.

How does bleeding from the digestive tract cause a low blood count?

Non-menstruating women with a blood count below 36%, and men with a blood count below 38% should see their physician for further evaluation if they donate blood fewer than 3 times per year and are not already under care for a chronic illness or condition of the digestive tract.

Any form of bleeding reduces the number of red blood cells in your body and can lower your blood count. When you are healthy, small amounts of blood loss will not cause anemia because the body will recognize the need to produce more red blood cells, keeping your blood count steady. If your body is not able to produce red blood cells normally, or if the blood is leaving the body quicker than it can be replaced, anemia may develop.

In addition to causing blood loss, conditions of the digestive tract can reduce the body's ability to produce red blood cells. This can occur either by not having enough of the regulatory protein erythropoietin or by not supplying enough of the blood components, like iron.19 In many cases, your body's response to the illness, called inflammation, can stop iron from playing its normal role in making new red blood cells.

How can I tell if my low blood count is due to bleeding?

Signs of bleeding or symptoms of anemia should be taken seriously because they are often the first indications you may have a condition of the digestive tract. Some symptoms of anemia to watch for include fatigue, weakness, pale skin, chest pain, dizziness, irritability, numbness or coldness in your hands and feet, trouble breathing, a fast heartbeat, and headache.19

The best way to determine if you have anemia is to discuss your blood count with your doctor. Your doctor can determine if you are bleeding from your digestive tract by performing a noninvasive fecal occult blood test, which checks the stool for signs of blood. It can chemically detect even small, invisible amounts of blood. Although not a common cause for low blood counts, if you believe you might be bleeding due to a condition of the digestive tract, be sure to make an appointment with your doctor without delay.

How do I treat a low blood count caused by bleeding?

It is important to talk with your doctor about changes in your health - to understand which problems can be treated and to discuss your treatment options. It can be difficult to tell if you are bleeding from your digestive tract because blood may not be visible in your stool. A doctor can help determine if you are bleeding and may identify the specific condition that is causing your low blood count. If the underlying condition can be effectively treated, the anemia often improves. If your body is also low in stored iron or vitamins, it is important to treat these deficiencies first. Close communication with your doctor will help him or her provide the treatment that is best for you based on what is causing the anemia.

If my low blood count is caused by bleeding, how can I prevent it from happening again?

Anemia often accompanies conditions that cause bleeding from the digestive tract. If you find out you have a low blood count or anemia, you may want to consult your doctor. Close communication with your doctor about your medications, symptoms, and low blood count will help him or her determine the best plan of action to prevent anemia. Additionally, it is important to eat a healthy, balanced diet and take any vitamins, multivitamins or supplements as directed by your doctor to prevent anemia caused by deficiencies.

After deciding on a treatment and prevention plan with your doctor and strictly following these recommendations, you may be healthy enough to donate blood once again.