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Anemia
Summary
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
National Heart, Lung, and Blood Institute
Encyclopedia
- Aase syndrome Medical Encyclopedia
- Anemia caused by low iron – children Medical Encyclopedia
- Antiparietal cell antibody test Medical Encyclopedia
- Bone marrow biopsy Medical Encyclopedia
- Donath-Landsteiner test Medical Encyclopedia
- Drug-induced immune hemolytic anemia Medical Encyclopedia
- Erythropoietin test Medical Encyclopedia
- Folate-deficiency anemia Medical Encyclopedia
- Haptoglobin blood test Medical Encyclopedia
- Hemoglobin C disease Medical Encyclopedia
- Hemoglobin electrophoresis Medical Encyclopedia
- Hemolytic anemia caused by chemicals and toxins Medical Encyclopedia
- Hemolytic crisis Medical Encyclopedia
- Hereditary spherocytic anemia Medical Encyclopedia
- Immune hemolytic anemia Medical Encyclopedia
- Lactate dehydrogenase test Medical Encyclopedia
- LDH isoenzyme blood test Medical Encyclopedia
- Paroxysmal cold hemoglobinuria (PCH) Medical Encyclopedia
- Paroxysmal nocturnal hemoglobinuria (PNH) Medical Encyclopedia
- Plummer-Vinson syndrome Medical Encyclopedia
- Pyruvate kinase blood test Medical Encyclopedia
- Pyruvate kinase deficiency Medical Encyclopedia
- Schilling test Medical Encyclopedia
- Serum free hemoglobin test Medical Encyclopedia
- Serum iron test Medical Encyclopedia
- Stool guaiac test Medical Encyclopedia
- Subacute combined degeneration Medical Encyclopedia
- Sugar-water hemolysis test Medical Encyclopedia
- Total iron binding capacity Medical Encyclopedia
Women
- Anemia March of Dimes Foundation
- Anemia Department of Health and Human Services, Office on Women’s Health
- Anemia and Pregnancy American Society of Hematology
Older Adults
- Anemia AGS Health in Aging Foundation
Treatments and Therapies
- Anemia American Society of Clinical Oncology
- Iron National Institutes of Health, Office of Dietary Supplements
- Treatments for Blood Disorders National Heart, Lung, and Blood Institute
- Vitamin B12 National Institutes of Health, Office of Dietary Supplements
Start Here
- Anemia American Academy of Family Physicians
- Anemia American Society of Hematology
- What Is Anemia? National Heart, Lung, and Blood Institute
- Your Guide to Anemia National Heart, Lung, and Blood Institute
Patient Handouts
- Anemia Medical Encyclopedia
- Anemia caused by low iron – infants and toddlers Medical Encyclopedia
- Anemia of chronic disease Medical Encyclopedia
- Anemia of Inflammation and Chronic Disease National Institute of Diabetes and Digestive and Kidney Diseases
- Febrile/cold agglutinins Medical Encyclopedia
- Ferritin blood test Medical Encyclopedia
- Hemolytic anemia Medical Encyclopedia
- Iron deficiency anemia Medical Encyclopedia
- Pernicious anemia Medical Encyclopedia
- Vitamin B12 deficiency anemia Medical Encyclopedia
- Vitamin B12 level Medical Encyclopedia
Children
- Anemia (For Parents) Nemours Foundation
- Anemia in the Newborn Merck & Co., Inc.
- Diamond-Blackfan Anemia (For Parents) Nemours Foundation
- Hereditary Spherocytosis (For Parents) Nemours Foundation
- Iron-Deficiency Anemia (For Parents) Nemours Foundation
- Pyruvate Kinase Deficiency (For Parents) Nemours Foundation
- What’s Anemia? (For Kids) Nemours Foundation
Teenagers
- Anemia (For Teens) Nemours Foundation
Specifics
- Anemia Due to Excessive Bleeding Merck & Co., Inc.
- Anemia of Inflammation or Chronic Disease National Institute of Diabetes and Digestive and Kidney Diseases
- Hemoglobin C, S-C, and E Diseases Merck & Co., Inc.
- Hemolytic Anemia National Heart, Lung, and Blood Institute
- Iron-Deficiency Anemia National Heart, Lung, and Blood Institute
- Paroxysmal Nocturnal Hemoglobinuria (PNH) Aplastic Anemia & MDS International Foundation
- Vitamin B12-Deficiency Anemia National Heart, Lung, and Blood Institute
- Vitamin Deficiency Anemia Mayo Foundation for Medical Education and Research
Related Issues
- Anemia in Chronic Kidney Disease National Institute of Diabetes and Digestive and Kidney Diseases
- Craving and Chewing Ice: A Sign of Anemia? Mayo Foundation for Medical Education and Research
- Low Red Blood Cell Counts (Anemia) American Cancer Society
Diagnosis and Tests
- Blood Smear National Library of Medicine
- Blood Tests National Heart, Lung, and Blood Institute
- Bone Marrow Test National Library of Medicine
- Complete Blood Count (CBC) National Library of Medicine
- Ferritin Blood Test National Library of Medicine
- Haptoglobin (HP) Test National Library of Medicine
- Hemoglobin Electrophoresis National Library of Medicine
- Iron Tests National Library of Medicine
- Lactate Dehydrogenase (LDH) Isoenzymes Test National Library of Medicine
- Lactate Dehydrogenase (LDH) Test National Library of Medicine
- Red Blood Cell (RBC) Indices National Library of Medicine
- Reticulocyte Count National Library of Medicine
- Vitamin B Test National Library of Medicine
Clinical Trials
- ClinicalTrials.gov: Anemia, Iron-Deficiency National Institutes of Health
Genetics
- Congenital dyserythropoietic anemia: MedlinePlus Genetics National Library of Medicine
- Diamond-Blackfan anemia: MedlinePlus Genetics National Library of Medicine
- Ghosal hematodiaphyseal dysplasia: MedlinePlus Genetics National Library of Medicine
- Glucose phosphate isomerase deficiency: MedlinePlus Genetics National Library of Medicine
- Hereditary folate malabsorption: MedlinePlus Genetics National Library of Medicine
- Hereditary spherocytosis: MedlinePlus Genetics National Library of Medicine
- Hypochromic microcytic anemia with iron overload: MedlinePlus Genetics National Library of Medicine
- Imerslund-Gräsbeck syndrome: MedlinePlus Genetics National Library of Medicine
- Iron-refractory iron deficiency anemia: MedlinePlus Genetics National Library of Medicine
- Majeed syndrome: MedlinePlus Genetics National Library of Medicine
- Mucolipidosis type IV: MedlinePlus Genetics National Library of Medicine
- Paroxysmal nocturnal hemoglobinuria: MedlinePlus Genetics National Library of Medicine
- Phosphoglycerate kinase deficiency: MedlinePlus Genetics National Library of Medicine
- Pyruvate kinase deficiency: MedlinePlus Genetics National Library of Medicine
- Thiamine-responsive megaloblastic anemia syndrome: MedlinePlus Genetics National Library of Medicine
- TRNT1 deficiency: MedlinePlus Genetics National Library of Medicine
- X-linked sideroblastic anemia: MedlinePlus Genetics National Library of Medicine
Statistics and Research
- FastStats: Anemia or Iron Deficiency National Center for Health Statistics
Find an Expert
- National Heart, Lung, and Blood Institute National Heart, Lung, and Blood Institute
- National Institute of Diabetes and Digestive and Kidney Diseases National Institute of Diabetes and Digestive and Kidney Diseases