Anemia
Anemia occurs when there aren't enough healthy red blood cells to carry oxygen to your body's organs.Nutritional anemias

Pernicious anemia: Pernicious anemia, one of the causes of vitamin B12 deficiency, is an autoimmune condition that prevents your body from absorbing vitamin B12.Women and people designated female at birth (DFAB): Women and people DFAB who have heavy periods (menstrual bleeding) or conditions like uterine fibroids may lose blood and develop anemia.Contents
Overview
Symptoms and Causes
Diagnosis and Tests
Management and Treatment
Prevention
Outlook / Prognosis
Living With
Overview
What is anemia?Inherited anemias

Sickle cell anemia: Sickle cell anemia changes your red blood cells' shape, turning round flexible discs into stiff and sticky sickle cells that block blood flow.Women who are pregnant: Women who are pregnant may develop iron-deficiency anemia, which may increase the chance of complications such as premature birth or giving birth to babies with low birth weight.People age 65 and older: People over 65 are more likely to have iron-poor diets and certain chronic diseases that increase their risk of developing anemia.Anemia is very common, affecting an estimated one-third of the global population and an estimated 3 million people in the United States.Iron-deficiency anemia: As its name implies, iron-deficiency anemia happens when your body doesn't have enough iron to make hemoglobin.Megaloblastic anemia: Megaloblastic anemia is a type of vitamin deficiency anemia that happens when you don't get enough vitamin B12 and/or vitamin B9 (folate).Diamond-Blackfan anemia: This inherited disorder keeps your bone marrow from making enough red blood cells.Autoimmune hemolytic anemia: In autoimmune hemolytic anemia, your immune system attacks your red blood cells.Fatigue -- feeling too tired to manage your activities -- is the most noticeable anemia symptom.Fast or irregular heartbeat (arrhythmia): This is when your heart feels like it's racing or skipping beats.Anemia affects different people in different ways:

Newborns: Some infants are born with low red blood cell counts.Most newborns don't need medical treatment for anemia, but some with severe anemia may need blood transfusions.Children with anemia may develop related problems such as delayed development of motor skills and issues with learning.People with chronic conditions: Some chronic conditions like autoimmune diseases or cancer may increase the risk of anemia.Anemias caused by abnormal red blood cells

Hemolytic anemia: In this anemia, your red blood cells break down or die faster than usual.Macrocytic anemia: This anemia happens when your bone marrow makes unusually large red blood cells.Normocytic anemia: In this type of anemia, you have fewer red blood cells than usual, and those red blood cells don't have the normal amount of hemoglobin.When someone develops anemia, they're said to be anemic, meaning they have symptoms of anemia, like being very tired or feeling cold all of the time.