Anemia
Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.
Source: MedlinePlus, National Library of Medicine. Read the original source
MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.
If you have anemia, your blood does not carry enough oxygen to the rest of your body. The most common cause of anemia is not having enough iron. Your body needs iron to make hemoglobin. Hemoglobin is an iron-rich protein that gives the red color to blood. It carries oxygen from the lungs to the rest of the body.
Anemia has three main causes: blood loss, lack of red blood cell production, and high rates of red blood cell destruction.
Conditions that may lead to anemia include:
- Heavy periods
- Pregnancy
- Ulcers
- Colon polyps or colon cancer
- Inherited disorders
- A diet that does not have enough iron, folic acid or vitamin B12
- Blood disorders such as sickle cell anemia and thalassemia, or cancer
- Aplastic anemia, a condition that can be inherited or acquired
- G6PD deficiency, a metabolic disorder
Anemia can make you feel tired, cold, dizzy, and irritable. You may be short of breath or have a headache.
Your doctor will diagnose anemia with a physical exam and blood tests. Treatment depends on the kind of anemia you have.
NIH: National Heart, Lung, and Blood Institute
Symptoms, tests and care options
Further reading selected by MedlinePlus. Links open the original organizations’ websites.
- Anemia Diagnosis · National Heart, Lung, and Blood Institute
- Anemia Symptoms · National Heart, Lung, and Blood Institute
- Anemia Treatment and Management · National Heart, Lung, and Blood Institute
- Blood Smear · National Library of Medicine
- Blood Tests · National Heart, Lung, and Blood Institute
- Iron · National Institutes of Health, Office of Dietary Supplements
- Treatments for Blood Disorders · National Heart, Lung, and Blood Institute
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For a life-threatening emergency, call 911 in the U.S. or your local emergency number.
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