Anemia, also known as "low blood" or "tired blood," is the general term given to a medical condition in which the body doesn't make enough healthy red blood cells. All forms of anemia, including mild anemia, have similar symptoms and characteristics, but the difference is in their underlying causes. You may not have enough red blood cells, or the ones you do have may be abnormally-shaped and useless.
There are two major nutritional causes of anemia: B12 and iron deficiency. A deficiency in another B vitamin, called folate, can also cause anemia. If you suspect that you have anemia, your doctor can order simple blood tests to measure the number of red blood cells in your body and your nutritional status of iron, B12 and folate.
Your Blood Basics
Your blood contains four major component — red blood cells, white blood cells, platelets and plasma — that work together to carry out five major functions:
- Transportation of oxygen and other nutrients
- Regulation of body temperature
- Blood clotting to prevent excess blood loss
- Removal of carbon dioxide and other waste products
- Transportation of compounds, like antibodies, that help fight off disease and infection
Red blood cells, also called erythrocytes, make up the majority of your blood, or about 40 to 45 percent of its volume, according to the American Society of Hematology. The major function of your red blood cells is to carry oxygen from your lungs to the rest of your body's tissues and then remove carbon dioxide and other waste products. Oxygen attaches to a protein-rich component, called hemoglobin, in the center of the red blood cell.
How Does Anemia Develop?
Red blood cells are made in your bone marrow. Because of their unique structure, red blood cells only live for about 120 days. As red blood cells die, new ones are made to take their place, during a process called erythropoiesis. In order for your body to create healthy red blood cells, it needs access to various compounds, including iron, vitamin B12 and folate.
If there aren't adequate amounts of one or all of these nutrients in your system, you either won't be able to make enough red blood cells, or the ones you do make will be unhealthy and unable to carry out their normal functions. If this continues for an extended period of time, your total red blood cell count drops, as does your oxygen level, and you develop anemia.
According to the American Society of Hematology, anemia is the most common blood disorder, affecting more than three million Americans at any given time.
B12 Anemia vs. Iron Anemia
When it comes to B12 anemia vs. iron anemia, iron deficiency anemia is the most common type, according to the University of Rochester Medical Center. The condition develops if you don't take in enough iron through your diet or if you have a condition that affects iron absorption, like Crohn's disease, celiac disease or ulcerative colitis. Chronic blood loss, from a heavy menstrual cycle, or sudden blood loss, from trauma or internal bleeding — including gastrointestinal bleeding — also cause iron-deficiency anemia.
As with iron-deficiency anemia, a lack of vitamin B12 can also cause your body to make fewer healthy red blood cells. This type of anemia, called pernicious anemia or megaloblastic anemia, is characterized by red blood cells that are larger than they should be and oval-shaped, instead of round. Because of their abnormal size and shape, they're not able to carry oxygen as effectively, and they die sooner than healthy red blood cells.
One of the most common causes of vitamin B12 deficiency anemia is a lack of intrinsic factor, a protein in the stomach that's vital to the proper absorption of vitamin B12. Low levels of intrinsic factor are connected to other conditions, like gastritis, prior stomach surgery and autoimmune diseases. Intestinal surgery can also cause vitamin B12 deficiency anemia.
Folate is another B vitamin that's essential to healthy red blood cell production. If you don't have enough folate in your body, you can develop the same type of anemia that you would with a vitamin B12 deficiency. The most common causes of folate-deficiency anemia are:
Symptoms of Anemia
Because unhealthy red blood cells are a characteristic of all forms of anemia, the symptoms are the same across the board. If you have mild anemia, you may not notice any obvious symptoms, but as the condition gets more severe, it can cause things like:
- Pale skin
- Cold hands and feet
- Shortness of breath
- Irregular heartbeat
- Chest pain
- Difficulty concentrating
Treatment for Anemia
The specific treatment for anemia depends on the underlying cause, but the pattern is generally the same. If you or your doctor suspect you have anemia, the first step is usually a blood test that can measure the number of red blood cells in your blood. If numbers are low, further blood testing can be done to figure out whether it's iron or one of the B vitamins (or a combination of all of the above) that's causing your deficiency.
Once your doctor has determined that you do have anemia and which nutrient deficiency is causing it, the next step may be to look for any underlying causes of the deficiency. For example, celiac disease, an autoimmune condition characterized by a severe intolerance to gluten that damages the gastrointestinal tract, leading to malabsorption of nutrients. Because of this, celiac disease may be connected to all types of anemia.
If your doctor uncovers an underlying medical disorder that's connected to your anemia, she will develop a treatment plan to correct that and your nutritional status. If no underlying cause is found, your doctor may recommend that you take in more iron, vitamin B12 and folate through your diet or supplements.
Increasing Dietary Iron
If you have iron-deficiency anemia, your doctor may recommend getting more of the mineral in your diet. You can increase by eating a variety of iron-rich foods:
- White beans
- Dark chocolate
- Beef and beef liver
Keep in mind that your body can absorb the iron found in animal foods more easily than it can absorb the iron found in plant foods, so try not to rely strictly on vegetarian sources of iron, if possible. Or combine your vegetarian sources with foods rich in vitamin C, such as orange juice, red peppers, or tomatoes, with your iron-rich foods to enhance absorption.
Increasing B Vitamin Intake
If your anemia is due to a lack of one of the B vitamins, it's likely that you'll need to up your intake of foods that are good sources of each. The best dietary sources of vitamin B12 include:
- Beef and beef liver
- Rainbow trout
Some foods that are high in vitamin B12, like beef and beef liver, are also high in folate, but in order to make sure your meeting your needs for all nutrients, it's best to include a wide variety of foods in your diet. Other foods that are high in folate are:
- Black-eyed peas
- Brussels sprouts
- Romaine lettuce
- Mustard greens
- Green peas
- Kidney beans
- Wheat germ
- American Society of Hematology: "Anemia"
- National Heart, Lung and Blood Institute: "Anemia"
- Lab Tests Online: "Anemia"
- American Society of Hematology: "Iron-Deficiency Anemia"
- National Heart, Lung and Blood Institute: "Iron-Deficiency Anemia"
- John Hopkins Medicine: "Vitamin B12 Deficiency Anemia"
- Cedars-Sinai: "Vitamin B12 Deficiency Anemia"
- University of Michigan: Michigan Medicine: "Vitamin B12 Deficiency Anemia"
- National Heart, Lung and Blood Institute: "Pernicious Anemia"
- Johns Hopkins Medicine: "Folate-Deficiency Anemia"
- University of Rochester Medical Center: "What Are Red Blood Cells?"
- Merck Manual: "Red Blood Cell Production"
- American Society of Hematology: "Blood Basics"
- National Institutes of Health: Office of Dietary Supplements: "Iron"
- National Institutes of Health: Office of Dietary Supplements: "Vitamin B12"
- National Institutes of Health: Office of Dietary Supplements: "Folate"
- National Institutes of Health: Office of Dietary Supplements: "Vitamin C"