Anemia is diagnosed as any condition in which our body does not produce enough healthy red blood cells. The condition has been discovered to date back to more than 4,000 years ago and is the most common blood disorder.
Anemia currently affects more than 3 million Americans and an estimated 1.62 billion people in the world.1 Anemia is not strictly a disease, but a disorder. It is often a byproduct of other diseases that disrupt the body's ability to produce healthy red blood cells.
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Fast facts on anemia
Here are some key points on anemia. More detail and supporting information is in the main article.
- Globally, anemia affects an estimated 1.62 billion people, this accounts for 24.8% of the world's population.
- Pre-school children are at the most risk of the condition, with an estimated 47% suffering from the disease.
- There are currently more than 400 types of Anemia identified.
- Iron deficiency anemia is the most common type of blood disorder worldwide.
- Iron rich foods to combat anemia include meat, fish, mussels and oysters.
- Anemia is not restricted to humans and can affect cats and dogs.
- In developing countries every second pregnant woman and about 40% of preschool children are estimated to be anemic.2
- Individuals can have a mild form of anemia and, therefore, show little to no symptoms.
- Fatigue is the most common symptom of anemia, regardless of type.3
What is anemia?
Anemia is diagnosed as any condition in which our body does not produce enough healthy red blood cells.
Red blood cells are critical to our body's well-being. They carry hemoglobin, a complex protein that contains iron molecules. The main function of these molecules is to carry adequate oxygen from the lungs to the rest of your body.
If your body is not supported by enough red blood cells, then you may experience symptoms such as feeling tired or weak.
There are more than 400 types of Anemia currently known and these are divided into three main groups according to their cause.
- Anemia caused by blood loss
- Anemia caused by decreased or faulty red blood cells
- Anemia caused by the destruction of red blood cells.
The video below from the American Society of Hematology visualizes the importance of red blood cells in the body.
Causes of anemia
Unfortunately, there is no one specific cause of anemia. Due to the sheer number of anemia types, it can sometimes be difficult to pinpoint the exact cause.
Below, is a general overview of the causes of anemia according to the three main causal groups:
1: Anemia caused by blood loss
The most common type of anemia - iron deficiency anemia - falls into this category. In this case, the disorder is brought on by a shortage of iron in the body, most often caused by blood loss that exceeds the production of new red blood cells.
The blood loss can be both rapid and chronic. Examples of rapid blood loss can include surgery, childbirth or a ruptured blood vessel.
Chronic blood loss is more frequent among patients diagnosed with anemia. Here, the blood loss can be a result of stomach ulcers, cancer or tumor. Women who undergo heavy menstrual bleeding may also be at risk of developing anemia.
When blood is lost, your body reacts by pulling water from tissues outside the bloodstream in an attempt to keep the blood vessels filled. This additional water dilutes the blood, and as a result, the concentration of red blood cells in your blood are fewer.
2: Anemia caused by decreased or faulty red blood cells
A patient's diet can be a cause of anemia. A lack of iron or vitamin-rich foods severely impacts the body's capacity to produce enough healthy red blood cells.
Individuals with anemia have far fewer healthy red blood cells.
Vegetarians are particularly at risk of anemia due to the elimination of meat and, therefore, its high iron content from the diet. However, there are other iron-rich foods and iron and vitamin supplements available for patients undergoing a restricted diet.
Located in the center of our bones, the bone marrow is an essential component to the development of healthy red blood cells. The soft sponge-like tissue produces stem cells, which in turn, develop red blood cells, white blood cells, and platelets.
Bone marrow can be affected by a number of diseases such as leukemia, where abnormal white blood cells are produced. The production of healthy red blood cells is hampered without healthy bone marrow.
3: Anemia caused by the destruction of red blood cells
Red blood cells typically have a life span of 120 days in the bloodstream,4 but they can be destroyed or removed beforehand.
One type of anemia that falls under this category is autoimmune hemolytic anemia. This is characterized by the body's immune system mistakenly identifying its own red blood cells as a foreign substance and subsequently producing antibodies.
Symptoms of anemia
The most common symptom of anemia, regardless of type, is a feeling of fatigue and a lack of energy.
Other common symptoms of anemia may include:
- Paleness of skin
- Fast or irregular heartbeat
- Shortness of breath
- Chest pain
It is possible for patients to have a mild form of anemia and they may, therefore, show little to no symptoms. Some forms of anemia can have specific symptoms unique to its type:5
- Aplastic anemia - individuals can suffer from nausea and skin rashes
- Folic acid deficiency anemia - symptoms can include irritability, diarrhea, and a smooth tongue
- Hemolytic anemia - individuals may display signs of jaundice. Leg ulcers and abdominal pains are signs to this type of anemia
- Sickle cell anemia - early symptoms can include a painful swelling of the feet and hands, fatigue and jaundice.
On the next page we look at how anemia is diagnosed, the possible treatments for anemia and complications associated with the condition.