What is Iron Deficiency Anemia Secondary to Inadequate Dietary Iron Intake?
The World Health Organization regards a deficiency in the mineral iron as the top nutritional disorder in the world. Research suggests that as many as 80 percent of people in the world do not have enough iron in their bodies (WHO, 2008).
Without enough iron, your body will make fewer RBCs or will produce RBCs that are smaller than normal. This leads to “iron deficiency anemia secondary to inadequate dietary iron intake”—in other words, anemia that is caused by not eating enough foods that contain iron.
Anemia is a medical condition where person has lower than normal levels of red blood cells (RBCs) in his or her blood. It can cause headaches, weakness, and many other symptoms, and can also lead to long-term health problems if it is not treated.
There are many causes of anemia, but iron deficiency anemia is the most common type of anemia. According to the WHO, as many as 30 percent of people in the world have anemia due to prolonged iron deficiency (WHO, 2008).
There are many reasons why someone might not get enough iron in their diet. A good source of iron is meat. Vegetarians or vegans who do not replace meat with another iron-rich food are at risk for iron deficiency anemia secondary to inadequate dietary iron intake. People who eat a poor or restricted diet low in fruits, vegetables, and meat are also at a high risk.
Causes of Iron Deficiency Anemia Secondary to Inadequate Dietary Iron Intake
Iron deficiency is the most common nutritional deficiency in the U.S. It is also the most common cause of anemia (CDC, 2011). Iron deficiency anemia secondary to inadequate dietary iron intake is caused by consuming a diet low in iron-rich foods. The best source of iron in foods is from meat, fish, and foods that are fortified with additional iron.
Iron is required for healthy, functioning RBCs. An iron-containing protein in the RBCs called hemoglobin is responsible for carrying the oxygen in blood from the lungs to the rest of the body. Your body needs iron to produce hemoglobin. Without hemoglobin, your body will stop producing healthy RBCs. Your body will store some iron, but the stored iron will get used up quickly unless it is replaced by iron in the foods you eat.
The following groups of people are at a higher risk of eating a diet that is low in iron:
- vegetarians or vegans who do not replace meat with another iron-rich food
- people with an eating disorder
- people who are poor or homeless and do not have easy access to food
- people who live in urban ‘food deserts’ where healthy, affordable food is not available
- elderly people who do not eat a complete or diverse diet
- young children who drink a lot of cow’s milk (cow’s milk is low in iron)
- people on a weight loss diet
Symptoms of Iron Deficiency Anemia
Iron deficiency anemia can be very mild at first. The symptoms may go completely unnoticed. Most people do not realize they have anemia until it is found on a routine blood test (ASH, 2010).
Symptoms that may appear as the deficiency increases include:
- pale skin
- shortness of breath
- brittle nails
- fast heartbeat
- strange cravings for ice or dirt (pica)
- cold hands and feet
- tingling or a crawling-feeling in the legs
Diagnosis of Iron Deficiency Anemia
A doctor can diagnose anemia with blood tests. These include:
Complete Blood Count (CBC) Test
A test called a complete blood count (CBC) is usually the first test a doctor will use. A CBC measures the amount of all components of the blood. The blood components include:
- red blood cells (RBCs)
- white blood cells (WBCs)
- hematocrit: blood test that measures the percentage of total blood volume that is made up of RBCs
- platelets: component of blood that helps the blood clot
The CBC test provides information about your blood that is helpful in diagnosing iron deficiency anemia. This information includes:
- hematocrit levels
- hemoglobin levels
- size of your RBCs
In iron deficiency anemia, hematocrit and hemoglobin levels are low. RBCs are usually smaller in size than normal.
A CBC test is often performed as part of a routine physical examination. It is a good indicator of a person’s overall health. It may also be performed routinely before surgery. Diagnosis of this type of anemia is useful because most anemic people do not realize they are iron-deficient.
Anemia can usually be confirmed with a CBC. Your doctor might order other blood tests to find out the severity of your anemia and how to treat it. He or she may also examine your blood under a microscope. These tests will provide information including:
- RBC size and color (RBCs are pale if they are deficient in iron)
- ferritin levels: Ferritin helps with iron storage in your body. Low levels of ferritin indicate low iron storage.
- iron level in your blood
- total iron-binding capacity: A test to determine the amount of a protein called transferrin that is carrying iron. People with iron deficiency will have a large amount of transferrin that is not transporting iron.
If you are eating a poor diet, it’s likely that you are also deficient in other vitamins and minerals. Your doctor may order several other blood tests to determine if you are deficient in anything else. This may include blood tests for folic acid and vitamin B12 deficiency.
Potential Complications of Iron Deficiency Anemia
Most cases of anemia caused by iron deficiency are mild and do not cause complications. However, if iron is not added back into the diet, it can lead to other health problems.
If you have anemia, your heart must pump more blood to compensate for the low amount of oxygen. Heart failure or an enlarged heart muscle may occur if the iron deficiency is not reversed.
In severe cases of iron deficiency in pregnant women, a child may be born prematurely or at a low birth weight. Most pregnant women take iron supplements as part of their prenatal care to prevent this from happening.
Infants and children severely deficient in iron may experience a delay in their growth and development. They may also be more susceptible to infections.
Treatment of Iron Deficiency Anemia Secondary to Inadequate Dietary Iron Intake
Iron tablets can help restore iron levels in your body. If possible, you should take the iron tablets on an empty stomach to improve absorption, but they can be taken with meals if they upset your stomach. You may need to take the supplements for several months. Iron supplements may cause constipation or stools that are black in color.
If your doctor determines that you are also deficient in other vitamins and minerals, he or she may also prescribe other vitamins or a multivitamin.
Diets high in red meat, dark leafy vegetables, dried fruits and nuts, iron-fortified cereals, or bread can help treat or prevent iron deficiency.
Vitamin C helps your body absorb the iron you eat. If you are taking iron tablets, a doctor might suggest taking the tablets along with a source of vitamin C. A glass of orange juice is a good source of the vitamin.
Vegetarians and vegans should make sure they are eating enough beans, tofu, dried fruits, spinach, and other dark vegetables. They should try to incorporate iron-fortified foods into their diet often. According to the National Institutes of Health’s Office of Dietary Supplements, vegetarians who do not eat any animal products may need nearly twice as much iron each day as people who eat animal products (NIH ODS, 2010). This is because iron in plant foods may not be absorbed as easily or completely as iron found in animal products, such as meat.
Your doctor may also refer you to a dietitian or nutritionist. These are specialists who are trained in healthy eating. A nutritionist can help to make sure you are getting all the necessary vitamins and minerals from the foods you eat.
People with an eating disorder may need to speak with a nutritionist who specializes in eating disorders to discuss their long-term treatment options.
In the most severe cases, a blood transfusion can replace iron quickly. This procedure involves receiving blood through an intravenous (IV) line, which is inserted into a blood vessel.
Prevention of Iron Deficiency Anemia Secondary to Inadequate Dietary Iron Intake
You should eat a diet high in iron-rich foods and vitamin C to prevent low blood iron levels. Mothers should make sure to feed their babies either breast milk or iron-fortified infant formula.
Foods high in iron include:
- meat, such as lamb, pork, chicken, and beef
- pumpkin and squash seeds
- leafy greens, such as spinach
- raisins and other dried fruit
- seafood, such as clams, sardines, shrimp, and oysters
- iron-fortified dry and instant cereals
Foods high in vitamin C include:
- citrus fruits, such as oranges, grapefruit, strawberries, kiwis, guava, papaya, pineapple, melons and mango
- red and green bell peppers
- Brussels sprouts
- leafy greens