Anemia: Causes

What causes anemia?

Anemia is an abnormal condition in which there is a low number of red blood cells in the blood. Anemia can be caused by a variety of diseases, disorders and conditions.

Bleeding and hemorrhage

Bleeding is the most common cause of anemia. Severe, uncontrolled bleeding (hemorrhage), such as bleeding from ruptured esophageal varices, can rapidly lead to life-threatening anemia. Small amounts of repeated bleeding, such as bloody stools due to ulcerative colitis, can lead to anemia over time. Conditions that cause bleeding or hemorrhage include:

• Colorectal cancer

• Heavy or long menstrual periods or vaginal bleeding due to uterine cancer

• Hemophilia (a rare hereditary disorder in which blood does not clot normally)

• Perforated peptic ulcer

• Postoperative hemorrhage

• Postpartum hemorrhage

• Ruptured aortic aneurysm

• Ruptured esophageal varices

• Trauma, such as a pelvic fracture, spleen injury, or aortic rupture

Other causes of anemia

• Alcoholism

• Chemotherapy and medications for HIV/AIDS

• Chronic diseases, such as cancer, celiac disease, and kidney disease, which can hinder the body’s production of red blood cells

• Hemolytic anemia or sickle cell disease, in which the body destroys old red blood cells faster than it produces new ones

• Iron deficiency anemia and thalassemia, which cause a deficiency of hemoglobin in the red blood cells

• Pregnancy

• Vitamin B₁₂ deficiency (such as pernicious anemia), aplastic anemia, or a low level of the hormone erythropoietin, which impair the body’s normal production of red blood cells

What are the risk factors for anemia?

A number of factors increase the risk for anemia. Risk factors include:

• Alcoholism

• Being a woman of childbearing age

• Certain medications, such as chemotherapy or drugs for HIV/AIDS

• Chronic diseases such as cancer, celiac disease, and kidney disease

• Not eating a well-balanced diet that includes foods high in vitamin B, such as eggs, meats, and whole grains

Reducing your risk of anemia

You can lower your risk of some underlying causes of anemia by:

• Abstaining from alcohol or drinking in moderation: no more than two drinks per day for a man and one drink per day for a woman

• Eating a well-balanced diet that includes foods high in iron and vitamin B, such as eggs, meats, and whole grains

• Following your treatment plan for diseases, such as celiac disease, cancer, and kidney disease

• Seeking early and regular prenatal care